CVE-2024-26870 (GCVE-0-2024-26870)

Vulnerability from cvelistv5 – Published: 2024-04-17 10:27 – Updated: 2026-10-15 00:38
VLAI
Title
NFSv4.2: fix nfs4_listxattr kernel BUG at mm/usercopy.c:102
Summary
In the Linux kernel, the following vulnerability has been resolved: NFSv4.2: fix nfs4_listxattr kernel BUG at mm/usercopy.c:102 A call to listxattr() with a buffer size = 0 returns the actual size of the buffer needed for a subsequent call. When size > 0, nfs4_listxattr() does not return an error because either generic_listxattr() or nfs4_listxattr_nfs4_label() consumes exactly all the bytes then size is 0 when calling nfs4_listxattr_nfs4_user() which then triggers the following kernel BUG: [ 99.403778] kernel BUG at mm/usercopy.c:102! [ 99.404063] Internal error: Oops - BUG: 00000000f2000800 [#1] SMP [ 99.408463] CPU: 0 PID: 3310 Comm: python3 Not tainted 6.6.0-61.fc40.aarch64 #1 [ 99.415827] Call trace: [ 99.415985] usercopy_abort+0x70/0xa0 [ 99.416227] __check_heap_object+0x134/0x158 [ 99.416505] check_heap_object+0x150/0x188 [ 99.416696] __check_object_size.part.0+0x78/0x168 [ 99.416886] __check_object_size+0x28/0x40 [ 99.417078] listxattr+0x8c/0x120 [ 99.417252] path_listxattr+0x78/0xe0 [ 99.417476] __arm64_sys_listxattr+0x28/0x40 [ 99.417723] invoke_syscall+0x78/0x100 [ 99.417929] el0_svc_common.constprop.0+0x48/0xf0 [ 99.418186] do_el0_svc+0x24/0x38 [ 99.418376] el0_svc+0x3c/0x110 [ 99.418554] el0t_64_sync_handler+0x120/0x130 [ 99.418788] el0t_64_sync+0x194/0x198 [ 99.418994] Code: aa0003e3 d000a3e0 91310000 97f49bdb (d4210000) Issue is reproduced when generic_listxattr() returns 'system.nfs4_acl', thus calling lisxattr() with size = 16 will trigger the bug. Add check on nfs4_listxattr() to return ERANGE error when it is called with size > 0 and the return value is greater than size.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-05-28 19:56 UTC
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6820 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 012a211abd5db098094ce429de5f046368391e68 , < 4403438eaca6e91f02d272211c4d6b045092396b (git)
Affected: 012a211abd5db098094ce429de5f046368391e68 , < 9d52865ff28245fc2134da9f99baff603a24407a (git)
Affected: 012a211abd5db098094ce429de5f046368391e68 , < 06e828b3f1b206de08ef520fc46a40b22e1869cb (git)
Affected: 012a211abd5db098094ce429de5f046368391e68 , < 79cdcc765969d23f4e3d6ea115660c3333498768 (git)
Affected: 012a211abd5db098094ce429de5f046368391e68 , < 80365c9f96015bbf048fdd6c8705d3f8770132bf (git)
Affected: 012a211abd5db098094ce429de5f046368391e68 , < 23bfecb4d852751d5e403557dd500bb563313baf (git)
Affected: 012a211abd5db098094ce429de5f046368391e68 , < 251a658bbfceafb4d58c76b77682c8bf7bcfad65 (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.9
Unaffected: 0 , < 5.9 (semver)
Unaffected: 5.10.214 , ≤ 5.10.* (semver)
Unaffected: 5.15.153 , ≤ 5.15.* (semver)
Unaffected: 6.1.83 , ≤ 6.1.* (semver)
Unaffected: 6.6.23 , ≤ 6.6.* (semver)
Unaffected: 6.7.11 , ≤ 6.7.* (semver)
Unaffected: 6.8.2 , ≤ 6.8.* (semver)
Unaffected: 6.9 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem Affected: 0 , < V1.1.1 (custom)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2024-26870",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-05-28T19:56:13.503124Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2024-06-04T17:49:37.605Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      },
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-02T00:21:04.235Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/4403438eaca6e91f02d272211c4d6b045092396b"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/9d52865ff28245fc2134da9f99baff603a24407a"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/06e828b3f1b206de08ef520fc46a40b22e1869cb"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/79cdcc765969d23f4e3d6ea115660c3333498768"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/80365c9f96015bbf048fdd6c8705d3f8770132bf"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/23bfecb4d852751d5e403557dd500bb563313baf"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/251a658bbfceafb4d58c76b77682c8bf7bcfad65"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "affected": [
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC S7-1500 TM MFP - GNU/Linux subsystem",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "V1.1.1",
                "status": "affected",
                "version": "0",
                "versionType": "custom"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-10-15T00:38:55.474Z",
          "orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
          "shortName": "siemens-SADP"
        },
        "references": [
          {
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-265688.html"
          }
        ],
        "x_adpType": "supplier"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/nfs/nfs4proc.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "4403438eaca6e91f02d272211c4d6b045092396b",
              "status": "affected",
              "version": "012a211abd5db098094ce429de5f046368391e68",
              "versionType": "git"
            },
            {
              "lessThan": "9d52865ff28245fc2134da9f99baff603a24407a",
              "status": "affected",
              "version": "012a211abd5db098094ce429de5f046368391e68",
              "versionType": "git"
            },
            {
              "lessThan": "06e828b3f1b206de08ef520fc46a40b22e1869cb",
              "status": "affected",
              "version": "012a211abd5db098094ce429de5f046368391e68",
              "versionType": "git"
            },
            {
              "lessThan": "79cdcc765969d23f4e3d6ea115660c3333498768",
              "status": "affected",
              "version": "012a211abd5db098094ce429de5f046368391e68",
              "versionType": "git"
            },
            {
              "lessThan": "80365c9f96015bbf048fdd6c8705d3f8770132bf",
              "status": "affected",
              "version": "012a211abd5db098094ce429de5f046368391e68",
              "versionType": "git"
            },
            {
              "lessThan": "23bfecb4d852751d5e403557dd500bb563313baf",
              "status": "affected",
              "version": "012a211abd5db098094ce429de5f046368391e68",
              "versionType": "git"
            },
            {
              "lessThan": "251a658bbfceafb4d58c76b77682c8bf7bcfad65",
              "status": "affected",
              "version": "012a211abd5db098094ce429de5f046368391e68",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/nfs/nfs4proc.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.9"
            },
            {
              "lessThan": "5.9",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.214",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.153",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.83",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.23",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.7.*",
              "status": "unaffected",
              "version": "6.7.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.8.*",
              "status": "unaffected",
              "version": "6.8.2",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.9",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.214",
                  "versionStartIncluding": "5.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.153",
                  "versionStartIncluding": "5.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.83",
                  "versionStartIncluding": "5.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.23",
                  "versionStartIncluding": "5.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.7.11",
                  "versionStartIncluding": "5.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.8.2",
                  "versionStartIncluding": "5.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.9",
                  "versionStartIncluding": "5.9",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFSv4.2: fix nfs4_listxattr kernel BUG at mm/usercopy.c:102\n\nA call to listxattr() with a buffer size = 0 returns the actual\nsize of the buffer needed for a subsequent call. When size \u003e 0,\nnfs4_listxattr() does not return an error because either\ngeneric_listxattr() or nfs4_listxattr_nfs4_label() consumes\nexactly all the bytes then size is 0 when calling\nnfs4_listxattr_nfs4_user() which then triggers the following\nkernel BUG:\n\n  [   99.403778] kernel BUG at mm/usercopy.c:102!\n  [   99.404063] Internal error: Oops - BUG: 00000000f2000800 [#1] SMP\n  [   99.408463] CPU: 0 PID: 3310 Comm: python3 Not tainted 6.6.0-61.fc40.aarch64 #1\n  [   99.415827] Call trace:\n  [   99.415985]  usercopy_abort+0x70/0xa0\n  [   99.416227]  __check_heap_object+0x134/0x158\n  [   99.416505]  check_heap_object+0x150/0x188\n  [   99.416696]  __check_object_size.part.0+0x78/0x168\n  [   99.416886]  __check_object_size+0x28/0x40\n  [   99.417078]  listxattr+0x8c/0x120\n  [   99.417252]  path_listxattr+0x78/0xe0\n  [   99.417476]  __arm64_sys_listxattr+0x28/0x40\n  [   99.417723]  invoke_syscall+0x78/0x100\n  [   99.417929]  el0_svc_common.constprop.0+0x48/0xf0\n  [   99.418186]  do_el0_svc+0x24/0x38\n  [   99.418376]  el0_svc+0x3c/0x110\n  [   99.418554]  el0t_64_sync_handler+0x120/0x130\n  [   99.418788]  el0t_64_sync+0x194/0x198\n  [   99.418994] Code: aa0003e3 d000a3e0 91310000 97f49bdb (d4210000)\n\nIssue is reproduced when generic_listxattr() returns \u0027system.nfs4_acl\u0027,\nthus calling lisxattr() with size = 16 will trigger the bug.\n\nAdd check on nfs4_listxattr() to return ERANGE error when it is\ncalled with size \u003e 0 and the return value is greater than size."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The vulnerability is triggered by a local `listxattr(2)`/`llistxattr(2)`/`flistxattr(2)` syscall on a file residing on an NFSv4 mount; no network peer can initiate it on its own. Although the overflow content is supplied by the NFS server over the wire, a local syscall is required to reach the code, so the attack vector is Local.\nAC:L - Triggering is fully deterministic \u2014 the attacker probes with `size = 0`, then calls `listxattr()` with a size exactly equal to the generic handler list (16 bytes for `\"system.nfs4_acl\\0\"`), with no race to win and no memory-layout condition outside their control. The required config (CONFIG_NFS_V4_2, CONFIG_NFS_V4_SECURITY_LABEL, CONFIG_HARDENED_USERCOPY) is enabled by default on mainstream distributions, as demonstrated by the reporter reproducing on a stock Fedora 40 kernel.\nPR:L - Any unprivileged local user with ordinary access to a file on an existing NFSv4.2 mount can call `listxattr()` and set the `user.*` xattrs that become the overflow payload; no capabilities are needed. NFS-mounted home directories on shared/multi-user hosts make this a standard unprivileged-user reach.\nUI:N - The attacker performs every step \u2014 setting the xattrs and issuing the sized `listxattr()` call \u2014 with no action by any other user. The pre-existing NFS mount is an environmental property of the deployment, not an interaction the attacker must induce.\nS:U - The over-read, the leaked data, and the heap overflow all occur within the kernel\u0027s own memory and are delivered to the attacker\u0027s own process. No VM, IOMMU, or other security-authority boundary is crossed.\nC:H - When hardened usercopy is not enforcing, `copy_to_user()` transfers up to XATTR_LIST_MAX (64 KB) of kernel heap memory past a 16-byte kmalloc object directly into the attacker\u0027s buffer, with the over-read length controlled by how many `user.*` xattrs the attacker attaches to the file. This is a large, attacker-sized disclosure of adjacent slab contents including potential pointers and other tasks\u0027 data.\nI:H - The `size_t` underflow hands `nfs4_listxattr_nfs4_user()` a past-the-end pointer with an effectively unbounded length, and `decode_listxattrs()` then memcpy()s `user.\u003cattacker-chosen-name\u003e\\0` records past the end of a kmalloc-16 object in a loop until EOF. This is a heap buffer overflow with attacker-controlled content, length, and destination slab, which is a strong primitive for adjacent-object corruption and control-flow hijacking.\nA:H - The reported and reproducible outcome is `usercopy_abort()` calling `BUG()` at mm/usercopy.c:102 \u2014 a kernel oops that is a full panic on systems with `panic_on_oops` (common on embedded, automotive, and hardened deployments), repeatable at will by any local user. The heap overflow path additionally corrupts slab metadata and adjacent objects, causing further crashes."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T11:28:01.958Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/4403438eaca6e91f02d272211c4d6b045092396b"
        },
        {
          "url": "https://git.kernel.org/stable/c/9d52865ff28245fc2134da9f99baff603a24407a"
        },
        {
          "url": "https://git.kernel.org/stable/c/06e828b3f1b206de08ef520fc46a40b22e1869cb"
        },
        {
          "url": "https://git.kernel.org/stable/c/79cdcc765969d23f4e3d6ea115660c3333498768"
        },
        {
          "url": "https://git.kernel.org/stable/c/80365c9f96015bbf048fdd6c8705d3f8770132bf"
        },
        {
          "url": "https://git.kernel.org/stable/c/23bfecb4d852751d5e403557dd500bb563313baf"
        },
        {
          "url": "https://git.kernel.org/stable/c/251a658bbfceafb4d58c76b77682c8bf7bcfad65"
        }
      ],
      "title": "NFSv4.2: fix nfs4_listxattr kernel BUG at mm/usercopy.c:102",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2024-26870",
    "datePublished": "2024-04-17T10:27:30.756Z",
    "dateReserved": "2024-02-19T14:20:24.184Z",
    "dateUpdated": "2026-10-15T00:38:55.474Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2024-26870",
      "date": "2026-11-02",
      "epss": "0.00283",
      "percentile": "0.20897"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "fs/nfs/nfs4proc.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "4403438eaca6e91f02d272211c4d6b045092396b",
                    "status": "affected",
                    "version": "012a211abd5db098094ce429de5f046368391e68",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "9d52865ff28245fc2134da9f99baff603a24407a",
                    "status": "affected",
                    "version": "012a211abd5db098094ce429de5f046368391e68",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "06e828b3f1b206de08ef520fc46a40b22e1869cb",
                    "status": "affected",
                    "version": "012a211abd5db098094ce429de5f046368391e68",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "79cdcc765969d23f4e3d6ea115660c3333498768",
                    "status": "affected",
                    "version": "012a211abd5db098094ce429de5f046368391e68",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "80365c9f96015bbf048fdd6c8705d3f8770132bf",
                    "status": "affected",
                    "version": "012a211abd5db098094ce429de5f046368391e68",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "23bfecb4d852751d5e403557dd500bb563313baf",
                    "status": "affected",
                    "version": "012a211abd5db098094ce429de5f046368391e68",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "251a658bbfceafb4d58c76b77682c8bf7bcfad65",
                    "status": "affected",
                    "version": "012a211abd5db098094ce429de5f046368391e68",
                    "versionType": "git"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "fs/nfs/nfs4proc.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "5.9"
                  },
                  {
                    "lessThan": "5.9",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.10.*",
                    "status": "unaffected",
                    "version": "5.10.214",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.15.*",
                    "status": "unaffected",
                    "version": "5.15.153",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.1.*",
                    "status": "unaffected",
                    "version": "6.1.83",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.6.*",
                    "status": "unaffected",
                    "version": "6.6.23",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.7.*",
                    "status": "unaffected",
                    "version": "6.7.11",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.8.*",
                    "status": "unaffected",
                    "version": "6.8.2",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "6.9",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          },
          {
            "affectedData": [
              {
                "defaultStatus": "unknown",
                "product": "SIMATIC S7-1500 TM MFP - GNU/Linux subsystem",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "V1.1.1",
                    "status": "affected",
                    "version": "0",
                    "versionType": "custom"
                  }
                ]
              }
            ],
            "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "A73BE1C2-BC30-4A60-80F0-7975135EB641",
                    "versionEndExcluding": "5.10.214",
                    "versionStartIncluding": "5.9",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "ACB69438-845D-4E3C-B114-3140611F9C0B",
                    "versionEndExcluding": "5.15.153",
                    "versionStartIncluding": "5.11",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "121A07F6-F505-4C47-86BF-9BB6CC7B6C19",
                    "versionEndExcluding": "6.1.83",
                    "versionStartIncluding": "5.16",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "E00814DC-0BA7-431A-9926-80FEB4A96C68",
                    "versionEndExcluding": "6.6.23",
                    "versionStartIncluding": "6.2",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "9B95D3A6-E162-47D5-ABFC-F3FA74FA7CFD",
                    "versionEndExcluding": "6.7.11",
                    "versionStartIncluding": "6.7",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "543A75FF-25B8-4046-A514-1EA8EDD87AB1",
                    "versionEndExcluding": "6.8.2",
                    "versionStartIncluding": "6.8",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          },
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*",
                    "matchCriteriaId": "07B237A9-69A3-4A9C-9DA0-4E06BD37AE73",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFSv4.2: fix nfs4_listxattr kernel BUG at mm/usercopy.c:102\n\nA call to listxattr() with a buffer size = 0 returns the actual\nsize of the buffer needed for a subsequent call. When size \u003e 0,\nnfs4_listxattr() does not return an error because either\ngeneric_listxattr() or nfs4_listxattr_nfs4_label() consumes\nexactly all the bytes then size is 0 when calling\nnfs4_listxattr_nfs4_user() which then triggers the following\nkernel BUG:\n\n  [   99.403778] kernel BUG at mm/usercopy.c:102!\n  [   99.404063] Internal error: Oops - BUG: 00000000f2000800 [#1] SMP\n  [   99.408463] CPU: 0 PID: 3310 Comm: python3 Not tainted 6.6.0-61.fc40.aarch64 #1\n  [   99.415827] Call trace:\n  [   99.415985]  usercopy_abort+0x70/0xa0\n  [   99.416227]  __check_heap_object+0x134/0x158\n  [   99.416505]  check_heap_object+0x150/0x188\n  [   99.416696]  __check_object_size.part.0+0x78/0x168\n  [   99.416886]  __check_object_size+0x28/0x40\n  [   99.417078]  listxattr+0x8c/0x120\n  [   99.417252]  path_listxattr+0x78/0xe0\n  [   99.417476]  __arm64_sys_listxattr+0x28/0x40\n  [   99.417723]  invoke_syscall+0x78/0x100\n  [   99.417929]  el0_svc_common.constprop.0+0x48/0xf0\n  [   99.418186]  do_el0_svc+0x24/0x38\n  [   99.418376]  el0_svc+0x3c/0x110\n  [   99.418554]  el0t_64_sync_handler+0x120/0x130\n  [   99.418788]  el0t_64_sync+0x194/0x198\n  [   99.418994] Code: aa0003e3 d000a3e0 91310000 97f49bdb (d4210000)\n\nIssue is reproduced when generic_listxattr() returns \u0027system.nfs4_acl\u0027,\nthus calling lisxattr() with size = 16 will trigger the bug.\n\nAdd check on nfs4_listxattr() to return ERANGE error when it is\ncalled with size \u003e 0 and the return value is greater than size."
          },
          {
            "lang": "es",
            "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: NFSv4.2: corrige el ERROR del kernel nfs4_listxattr en mm/usercopy.c:102 Una llamada a listxattr() con un tama\u00f1o de b\u00fafer = 0 devuelve el tama\u00f1o real del b\u00fafer necesario para un convocatoria posterior. Cuando el tama\u00f1o \u0026gt; 0, nfs4_listxattr() no devuelve un error porque generic_listxattr() o nfs4_listxattr_nfs4_label() consume exactamente todos los bytes, entonces el tama\u00f1o es 0 al llamar a nfs4_listxattr_nfs4_user(), lo que luego activa el siguiente ERROR del kernel: [99.403778] ERROR del kernel en mm/usercopy.c:102! [99.404063] Error interno: Ups - ERROR: 00000000f2000800 [#1] SMP [99.408463] CPU: 0 PID: 3310 Comm: python3 No contaminado 6.6.0-61.fc40.aarch64 #1 [ 99.415827] Seguimiento de llamadas: [ 99.41 5985] usercopy_abort+0x70/0xa0 [ 99.416227] __check_heap_object+0x134/0x158 [ 99.416505] check_heap_object+0x150/0x188 [ 99.416696] __check_object_size.part.0+0x78/0x168 [ 99.416886 ] __check_object_size+0x28/0x40 [ 99.417078] listxattr+0x8c/0x120 [ 99.417252] path_listxattr+0x78/0xe0 [ 99.417476] __arm64_sys_listxattr+0x28/0x40 [ 99.417723] invoke_syscall+0x78/0x100 [ 99.417929] 48/0xf0 [ 99.418186] do_el0_svc+0x24/0x38 [ 99.418376] el0_svc+0x3c/ 0x110 [ 99.418554] el0t_64_sync_handler+0x120/0x130 [ 99.418788] el0t_64_sync+0x194/0x198 [ 99.418994] C\u00f3digo: aa0003e3 d000a3e0 91310000 97f49bdb (d42 10000) El problema se reproduce cuando generic_listxattr() devuelve \u0027system.nfs4_acl\u0027, llamando as\u00ed a lisxattr() con tama\u00f1o = 16 activar\u00e1 el error. Agregue verificaci\u00f3n en nfs4_listxattr() para devolver el error ERANGE cuando se llama con un tama\u00f1o \u0026gt; 0 y el valor de retorno es mayor que el tama\u00f1o."
          }
        ],
        "id": "CVE-2024-26870",
        "lastModified": "2026-10-15T01:17:26.880",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 7.8,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 5.9,
              "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
              "type": "Secondary"
            },
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 5.5,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 3.6,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2024-26870",
                "options": [
                  {
                    "exploitation": "none"
                  },
                  {
                    "automatable": "no"
                  },
                  {
                    "technicalImpact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-05-28T19:56:13.503124Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2024-04-17T11:15:09.460",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/06e828b3f1b206de08ef520fc46a40b22e1869cb"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/23bfecb4d852751d5e403557dd500bb563313baf"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/251a658bbfceafb4d58c76b77682c8bf7bcfad65"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/4403438eaca6e91f02d272211c4d6b045092396b"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/79cdcc765969d23f4e3d6ea115660c3333498768"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/80365c9f96015bbf048fdd6c8705d3f8770132bf"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/9d52865ff28245fc2134da9f99baff603a24407a"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/06e828b3f1b206de08ef520fc46a40b22e1869cb"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/23bfecb4d852751d5e403557dd500bb563313baf"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/251a658bbfceafb4d58c76b77682c8bf7bcfad65"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/4403438eaca6e91f02d272211c4d6b045092396b"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/79cdcc765969d23f4e3d6ea115660c3333498768"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/80365c9f96015bbf048fdd6c8705d3f8770132bf"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/9d52865ff28245fc2134da9f99baff603a24407a"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Mailing List"
            ],
            "url": "https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html"
          },
          {
            "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-265688.html"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Modified",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "NVD-CWE-noinfo"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-04T19:09:29+00:00",
      "cve": "CVE-2024-26870",
      "id": "CVE-2024-26870",
      "initial_release_date": "2024-04-17T00:00:00+00:00",
      "product_status:fixed": "1209",
      "product_status:known_affected": "64",
      "product_status:known_not_affected": "17",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: NFSv4.2: fix nfs4_listxattr kernel BUG at mm/usercopy.c:102",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2024/cve-2024-26870.json",
      "version": "3"
    },
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "providerMetadata": {
              "dateUpdated": "2024-08-02T00:21:04.235Z",
              "orgId": "af854a3a-2127-422b-91ae-364da2661108",
              "shortName": "CVE"
            },
            "references": [
              {
                "tags": [
                  "x_transferred"
                ],
                "url": "https://git.kernel.org/stable/c/4403438eaca6e91f02d272211c4d6b045092396b"
              },
              {
                "tags": [
                  "x_transferred"
                ],
                "url": "https://git.kernel.org/stable/c/9d52865ff28245fc2134da9f99baff603a24407a"
              },
              {
                "tags": [
                  "x_transferred"
                ],
                "url": "https://git.kernel.org/stable/c/06e828b3f1b206de08ef520fc46a40b22e1869cb"
              },
              {
                "tags": [
                  "x_transferred"
                ],
                "url": "https://git.kernel.org/stable/c/79cdcc765969d23f4e3d6ea115660c3333498768"
              },
              {
                "tags": [
                  "x_transferred"
                ],
                "url": "https://git.kernel.org/stable/c/80365c9f96015bbf048fdd6c8705d3f8770132bf"
              },
              {
                "tags": [
                  "x_transferred"
                ],
                "url": "https://git.kernel.org/stable/c/23bfecb4d852751d5e403557dd500bb563313baf"
              },
              {
                "tags": [
                  "x_transferred"
                ],
                "url": "https://git.kernel.org/stable/c/251a658bbfceafb4d58c76b77682c8bf7bcfad65"
              },
              {
                "tags": [
                  "x_transferred"
                ],
                "url": "https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html"
              }
            ],
            "title": "CVE Program Container"
          },
          {
            "affected": [
              {
                "defaultStatus": "unknown",
                "product": "SIMATIC S7-1500 TM MFP - GNU/Linux subsystem",
                "vendor": "Siemens",
                "versions": [
                  {
                    "lessThan": "V1.1.1",
                    "status": "affected",
                    "version": "0",
                    "versionType": "custom"
                  }
                ]
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2026-10-15T00:38:55.474Z",
              "orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
              "shortName": "siemens-SADP"
            },
            "references": [
              {
                "url": "https://cert-portal.siemens.com/productcert/html/ssa-265688.html"
              }
            ],
            "x_adpType": "supplier"
          },
          {
            "metrics": [
              {
                "other": {
                  "content": {
                    "id": "CVE-2024-26870",
                    "options": [
                      {
                        "Exploitation": "none"
                      },
                      {
                        "Automatable": "no"
                      },
                      {
                        "Technical Impact": "partial"
                      }
                    ],
                    "role": "CISA Coordinator",
                    "timestamp": "2024-05-28T19:56:13.503124Z",
                    "version": "2.0.3"
                  },
                  "type": "ssvc"
                }
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2024-05-28T19:56:20.156Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "defaultStatus": "unaffected",
              "product": "Linux",
              "programFiles": [
                "fs/nfs/nfs4proc.c"
              ],
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "vendor": "Linux",
              "versions": [
                {
                  "lessThan": "4403438eaca6e91f02d272211c4d6b045092396b",
                  "status": "affected",
                  "version": "012a211abd5db098094ce429de5f046368391e68",
                  "versionType": "git"
                },
                {
                  "lessThan": "9d52865ff28245fc2134da9f99baff603a24407a",
                  "status": "affected",
                  "version": "012a211abd5db098094ce429de5f046368391e68",
                  "versionType": "git"
                },
                {
                  "lessThan": "06e828b3f1b206de08ef520fc46a40b22e1869cb",
                  "status": "affected",
                  "version": "012a211abd5db098094ce429de5f046368391e68",
                  "versionType": "git"
                },
                {
                  "lessThan": "79cdcc765969d23f4e3d6ea115660c3333498768",
                  "status": "affected",
                  "version": "012a211abd5db098094ce429de5f046368391e68",
                  "versionType": "git"
                },
                {
                  "lessThan": "80365c9f96015bbf048fdd6c8705d3f8770132bf",
                  "status": "affected",
                  "version": "012a211abd5db098094ce429de5f046368391e68",
                  "versionType": "git"
                },
                {
                  "lessThan": "23bfecb4d852751d5e403557dd500bb563313baf",
                  "status": "affected",
                  "version": "012a211abd5db098094ce429de5f046368391e68",
                  "versionType": "git"
                },
                {
                  "lessThan": "251a658bbfceafb4d58c76b77682c8bf7bcfad65",
                  "status": "affected",
                  "version": "012a211abd5db098094ce429de5f046368391e68",
                  "versionType": "git"
                }
              ]
            },
            {
              "defaultStatus": "affected",
              "product": "Linux",
              "programFiles": [
                "fs/nfs/nfs4proc.c"
              ],
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "vendor": "Linux",
              "versions": [
                {
                  "status": "affected",
                  "version": "5.9"
                },
                {
                  "lessThan": "5.9",
                  "status": "unaffected",
                  "version": "0",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "5.10.*",
                  "status": "unaffected",
                  "version": "5.10.214",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "5.15.*",
                  "status": "unaffected",
                  "version": "5.15.153",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "6.1.*",
                  "status": "unaffected",
                  "version": "6.1.83",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "6.6.*",
                  "status": "unaffected",
                  "version": "6.6.23",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "6.7.*",
                  "status": "unaffected",
                  "version": "6.7.11",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "6.8.*",
                  "status": "unaffected",
                  "version": "6.8.2",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "*",
                  "status": "unaffected",
                  "version": "6.9",
                  "versionType": "original_commit_for_fix"
                }
              ]
            }
          ],
          "cpeApplicability": [
            {
              "nodes": [
                {
                  "cpeMatch": [
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "5.10.214",
                      "versionStartIncluding": "5.9",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "5.15.153",
                      "versionStartIncluding": "5.9",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.1.83",
                      "versionStartIncluding": "5.9",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.6.23",
                      "versionStartIncluding": "5.9",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.7.11",
                      "versionStartIncluding": "5.9",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.8.2",
                      "versionStartIncluding": "5.9",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "6.9",
                      "versionStartIncluding": "5.9",
                      "vulnerable": true
                    }
                  ],
                  "negate": false,
                  "operator": "OR"
                }
              ]
            }
          ],
          "descriptions": [
            {
              "lang": "en",
              "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFSv4.2: fix nfs4_listxattr kernel BUG at mm/usercopy.c:102\n\nA call to listxattr() with a buffer size = 0 returns the actual\nsize of the buffer needed for a subsequent call. When size \u003e 0,\nnfs4_listxattr() does not return an error because either\ngeneric_listxattr() or nfs4_listxattr_nfs4_label() consumes\nexactly all the bytes then size is 0 when calling\nnfs4_listxattr_nfs4_user() which then triggers the following\nkernel BUG:\n\n  [   99.403778] kernel BUG at mm/usercopy.c:102!\n  [   99.404063] Internal error: Oops - BUG: 00000000f2000800 [#1] SMP\n  [   99.408463] CPU: 0 PID: 3310 Comm: python3 Not tainted 6.6.0-61.fc40.aarch64 #1\n  [   99.415827] Call trace:\n  [   99.415985]  usercopy_abort+0x70/0xa0\n  [   99.416227]  __check_heap_object+0x134/0x158\n  [   99.416505]  check_heap_object+0x150/0x188\n  [   99.416696]  __check_object_size.part.0+0x78/0x168\n  [   99.416886]  __check_object_size+0x28/0x40\n  [   99.417078]  listxattr+0x8c/0x120\n  [   99.417252]  path_listxattr+0x78/0xe0\n  [   99.417476]  __arm64_sys_listxattr+0x28/0x40\n  [   99.417723]  invoke_syscall+0x78/0x100\n  [   99.417929]  el0_svc_common.constprop.0+0x48/0xf0\n  [   99.418186]  do_el0_svc+0x24/0x38\n  [   99.418376]  el0_svc+0x3c/0x110\n  [   99.418554]  el0t_64_sync_handler+0x120/0x130\n  [   99.418788]  el0t_64_sync+0x194/0x198\n  [   99.418994] Code: aa0003e3 d000a3e0 91310000 97f49bdb (d4210000)\n\nIssue is reproduced when generic_listxattr() returns \u0027system.nfs4_acl\u0027,\nthus calling lisxattr() with size = 16 will trigger the bug.\n\nAdd check on nfs4_listxattr() to return ERANGE error when it is\ncalled with size \u003e 0 and the return value is greater than size."
            }
          ],
          "metrics": [
            {
              "cvssV3_1": {
                "baseScore": 7.8,
                "baseSeverity": "HIGH",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                "version": "3.1"
              },
              "scenarios": [
                {
                  "lang": "en",
                  "value": "AV:L - The vulnerability is triggered by a local `listxattr(2)`/`llistxattr(2)`/`flistxattr(2)` syscall on a file residing on an NFSv4 mount; no network peer can initiate it on its own. Although the overflow content is supplied by the NFS server over the wire, a local syscall is required to reach the code, so the attack vector is Local.\nAC:L - Triggering is fully deterministic \u2014 the attacker probes with `size = 0`, then calls `listxattr()` with a size exactly equal to the generic handler list (16 bytes for `\"system.nfs4_acl\\0\"`), with no race to win and no memory-layout condition outside their control. The required config (CONFIG_NFS_V4_2, CONFIG_NFS_V4_SECURITY_LABEL, CONFIG_HARDENED_USERCOPY) is enabled by default on mainstream distributions, as demonstrated by the reporter reproducing on a stock Fedora 40 kernel.\nPR:L - Any unprivileged local user with ordinary access to a file on an existing NFSv4.2 mount can call `listxattr()` and set the `user.*` xattrs that become the overflow payload; no capabilities are needed. NFS-mounted home directories on shared/multi-user hosts make this a standard unprivileged-user reach.\nUI:N - The attacker performs every step \u2014 setting the xattrs and issuing the sized `listxattr()` call \u2014 with no action by any other user. The pre-existing NFS mount is an environmental property of the deployment, not an interaction the attacker must induce.\nS:U - The over-read, the leaked data, and the heap overflow all occur within the kernel\u0027s own memory and are delivered to the attacker\u0027s own process. No VM, IOMMU, or other security-authority boundary is crossed.\nC:H - When hardened usercopy is not enforcing, `copy_to_user()` transfers up to XATTR_LIST_MAX (64 KB) of kernel heap memory past a 16-byte kmalloc object directly into the attacker\u0027s buffer, with the over-read length controlled by how many `user.*` xattrs the attacker attaches to the file. This is a large, attacker-sized disclosure of adjacent slab contents including potential pointers and other tasks\u0027 data.\nI:H - The `size_t` underflow hands `nfs4_listxattr_nfs4_user()` a past-the-end pointer with an effectively unbounded length, and `decode_listxattrs()` then memcpy()s `user.\u003cattacker-chosen-name\u003e\\0` records past the end of a kmalloc-16 object in a loop until EOF. This is a heap buffer overflow with attacker-controlled content, length, and destination slab, which is a strong primitive for adjacent-object corruption and control-flow hijacking.\nA:H - The reported and reproducible outcome is `usercopy_abort()` calling `BUG()` at mm/usercopy.c:102 \u2014 a kernel oops that is a full panic on systems with `panic_on_oops` (common on embedded, automotive, and hardened deployments), repeatable at will by any local user. The heap overflow path additionally corrupts slab metadata and adjacent objects, causing further crashes."
                }
              ]
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-08-05T11:28:01.958Z",
            "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "shortName": "Linux"
          },
          "references": [
            {
              "url": "https://git.kernel.org/stable/c/4403438eaca6e91f02d272211c4d6b045092396b"
            },
            {
              "url": "https://git.kernel.org/stable/c/9d52865ff28245fc2134da9f99baff603a24407a"
            },
            {
              "url": "https://git.kernel.org/stable/c/06e828b3f1b206de08ef520fc46a40b22e1869cb"
            },
            {
              "url": "https://git.kernel.org/stable/c/79cdcc765969d23f4e3d6ea115660c3333498768"
            },
            {
              "url": "https://git.kernel.org/stable/c/80365c9f96015bbf048fdd6c8705d3f8770132bf"
            },
            {
              "url": "https://git.kernel.org/stable/c/23bfecb4d852751d5e403557dd500bb563313baf"
            },
            {
              "url": "https://git.kernel.org/stable/c/251a658bbfceafb4d58c76b77682c8bf7bcfad65"
            }
          ],
          "title": "NFSv4.2: fix nfs4_listxattr kernel BUG at mm/usercopy.c:102",
          "x_generator": {
            "engine": "bippy-1.2.0"
          }
        }
      },
      "cveMetadata": {
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "assignerShortName": "Linux",
        "cveId": "CVE-2024-26870",
        "datePublished": "2024-04-17T10:27:30.756Z",
        "dateReserved": "2024-02-19T14:20:24.184Z",
        "dateUpdated": "2026-10-15T00:38:55.474Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON

Loading timeline…




    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.