CVE-2026-98812 (GCVE-0-2026-98812)

Vulnerability from cvelistv5 – Published: 2026-10-18 15:48 – Updated: 2026-10-30 12:39
VLAI
Title
net/mctp: publish the mctp_dev only after it is initialised
Summary
In the Linux kernel, the following vulnerability has been resolved: net/mctp: publish the mctp_dev only after it is initialised mctp_add_dev() links the new mctp_dev into dev->mctp_ptr before mdev->dev is assigned, so a reader that picks the device up in that window dereferences a net_device pointer that is still NULL: KASAN: null-ptr-deref in range [0x00000000000000b0-0x00000000000000b7] Call Trace: <TASK> ? __pfx_mctp_sendmsg (./include/linux/sockptr.h:49) ? __pfx_mctp_dst_output (net/mctp/route.c:41) ? selinux_socket_sendmsg (security/selinux/hooks.c:5278) ____sys_sendmsg (net/socket.c:775 (discriminator 1) net/socket.c:790 (discriminator 1) net/socket.c:2684 (discriminator 1)) ? __pfx_____sys_sendmsg (net/socket.c:1131) ? __pfx_copy_msghdr_from_user (net/socket.c:2590) ? update_cfs_rq_load_avg (kernel/sched/fair.c:5478) ___sys_sendmsg (net/socket.c:2738) ? __pfx____sys_sendmsg (net/socket.c:2625) ? perf_event_task_tick (./include/linux/rcupdate.h:838) ? sched_tick (kernel/sched/core.c:5818) ? clockevents_program_event (kernel/time/clockevents.c:372) ? fdget (./include/linux/rcupdate.h:873 fs/file.c:1100) __sys_sendmsg (net/socket.c:2770) ? __pfx___sys_sendmsg (net/socket.c:2751) do_syscall_64 (arch/x86/entry/syscall_64.c:63) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121) </TASK> Fix by publishing only once the object is fully initialised: __mctp_dev_get() runs under rcu_read_lock() only and hands this object to readers as soon as mctp_ptr is assigned, so they must never observe mdev->dev == NULL.
Severity
No CVSS data available.
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 7018 records in the last 180 days details
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 583be982d93479ea3d85091b0fd0b01201ede87d , < 58a270b5ecd8629114a4754d642bad6a33bef493 (git)
Affected: 583be982d93479ea3d85091b0fd0b01201ede87d , < fdf09d0fa2fb639950bede185d22689f68df140e (git)
Affected: 583be982d93479ea3d85091b0fd0b01201ede87d , < 288ef37e0c463192dbb6436e61cdc07ce666dcb9 (git)
Affected: 583be982d93479ea3d85091b0fd0b01201ede87d , < af6e4f931afc2d670d133aa2bedc8b6e3753c618 (git)
Affected: 583be982d93479ea3d85091b0fd0b01201ede87d , < 63120572edde85bb2b70b0ed4d4817ed52247613 (git)
Affected: 583be982d93479ea3d85091b0fd0b01201ede87d , < f37f42e6e039a48c2dcf6c079b9f7fbc864ab7ef (git)
Affected: 583be982d93479ea3d85091b0fd0b01201ede87d , < aadf655e8ea9a8ffa24bb8d69f504572e8d18181 (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.15
Unaffected: 0 , < 5.15 (semver)
Unaffected: 5.15.224 , ≤ 5.15.* (semver)
Unaffected: 6.1.191 , ≤ 6.1.* (semver)
Unaffected: 6.6.160 , ≤ 6.6.* (semver)
Unaffected: 6.12.113 , ≤ 6.12.* (semver)
Unaffected: 6.18.56 , ≤ 6.18.* (semver)
Unaffected: 7.2.10 , ≤ 7.2.* (semver)
Unaffected: 7.3 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/mctp/device.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
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              "status": "affected",
              "version": "583be982d93479ea3d85091b0fd0b01201ede87d",
              "versionType": "git"
            },
            {
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              "versionType": "git"
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              "versionType": "git"
            }
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        },
        {
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          "programFiles": [
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          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
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              "version": "0",
              "versionType": "semver"
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            {
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              "status": "unaffected",
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              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.191",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.160",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.113",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.56",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.10",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.224",
                  "versionStartIncluding": "5.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.191",
                  "versionStartIncluding": "5.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.160",
                  "versionStartIncluding": "5.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.113",
                  "versionStartIncluding": "5.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.56",
                  "versionStartIncluding": "5.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.10",
                  "versionStartIncluding": "5.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3",
                  "versionStartIncluding": "5.15",
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                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mctp: publish the mctp_dev only after it is initialised\n\nmctp_add_dev() links the new mctp_dev into dev-\u003emctp_ptr before mdev-\u003edev\nis assigned, so a reader that picks the device up in that window\ndereferences a net_device pointer that is still NULL:\n\nKASAN: null-ptr-deref in range [0x00000000000000b0-0x00000000000000b7]\nCall Trace:\n \u003cTASK\u003e\n ? __pfx_mctp_sendmsg (./include/linux/sockptr.h:49)\n ? __pfx_mctp_dst_output (net/mctp/route.c:41)\n ? selinux_socket_sendmsg (security/selinux/hooks.c:5278)\n ____sys_sendmsg (net/socket.c:775 (discriminator 1) net/socket.c:790\n (discriminator 1) net/socket.c:2684 (discriminator 1))\n ? __pfx_____sys_sendmsg (net/socket.c:1131)\n ? __pfx_copy_msghdr_from_user (net/socket.c:2590)\n ? update_cfs_rq_load_avg (kernel/sched/fair.c:5478)\n ___sys_sendmsg (net/socket.c:2738)\n ? __pfx____sys_sendmsg (net/socket.c:2625)\n ? perf_event_task_tick (./include/linux/rcupdate.h:838)\n ? sched_tick (kernel/sched/core.c:5818)\n ? clockevents_program_event (kernel/time/clockevents.c:372)\n ? fdget (./include/linux/rcupdate.h:873 fs/file.c:1100)\n __sys_sendmsg (net/socket.c:2770)\n ? __pfx___sys_sendmsg (net/socket.c:2751)\n do_syscall_64 (arch/x86/entry/syscall_64.c:63)\n entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)\n \u003c/TASK\u003e\n\nFix by publishing only once the object is fully initialised:\n__mctp_dev_get() runs under rcu_read_lock() only and hands\nthis object to readers as soon as mctp_ptr is assigned, so\nthey must never observe mdev-\u003edev == NULL."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-30T12:39:58.094Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/58a270b5ecd8629114a4754d642bad6a33bef493"
        },
        {
          "url": "https://git.kernel.org/stable/c/fdf09d0fa2fb639950bede185d22689f68df140e"
        },
        {
          "url": "https://git.kernel.org/stable/c/288ef37e0c463192dbb6436e61cdc07ce666dcb9"
        },
        {
          "url": "https://git.kernel.org/stable/c/af6e4f931afc2d670d133aa2bedc8b6e3753c618"
        },
        {
          "url": "https://git.kernel.org/stable/c/63120572edde85bb2b70b0ed4d4817ed52247613"
        },
        {
          "url": "https://git.kernel.org/stable/c/f37f42e6e039a48c2dcf6c079b9f7fbc864ab7ef"
        },
        {
          "url": "https://git.kernel.org/stable/c/aadf655e8ea9a8ffa24bb8d69f504572e8d18181"
        }
      ],
      "title": "net/mctp: publish the mctp_dev only after it is initialised",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-98812",
    "datePublished": "2026-10-18T15:48:58.470Z",
    "dateReserved": "2026-09-25T10:25:14.371Z",
    "dateUpdated": "2026-10-30T12:39:58.094Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-98812",
      "date": "2026-11-01",
      "epss": "0.0018",
      "percentile": "0.07577"
    },
    "microsoft_vex": {
      "current_release_date": "2026-10-28T01:45:34.000Z",
      "cve": "CVE-2026-98812",
      "id": "msrc_CVE-2026-98812",
      "initial_release_date": "2026-10-20T01:06:28.000Z",
      "product_status:known_not_affected": "1",
      "product_status:under_investigation": "1",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "net/mctp: publish the mctp_dev only after it is initialised",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-98812.json",
      "version": "4"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "net/mctp/device.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "58a270b5ecd8629114a4754d642bad6a33bef493",
                    "status": "affected",
                    "version": "583be982d93479ea3d85091b0fd0b01201ede87d",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "fdf09d0fa2fb639950bede185d22689f68df140e",
                    "status": "affected",
                    "version": "583be982d93479ea3d85091b0fd0b01201ede87d",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "288ef37e0c463192dbb6436e61cdc07ce666dcb9",
                    "status": "affected",
                    "version": "583be982d93479ea3d85091b0fd0b01201ede87d",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "af6e4f931afc2d670d133aa2bedc8b6e3753c618",
                    "status": "affected",
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                    "versionType": "git"
                  },
                  {
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                    "status": "affected",
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                    "versionType": "git"
                  },
                  {
                    "lessThan": "f37f42e6e039a48c2dcf6c079b9f7fbc864ab7ef",
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                  },
                  {
                    "lessThan": "aadf655e8ea9a8ffa24bb8d69f504572e8d18181",
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                    "versionType": "git"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "net/mctp/device.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "5.15"
                  },
                  {
                    "lessThan": "5.15",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.15.*",
                    "status": "unaffected",
                    "version": "5.15.224",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.1.*",
                    "status": "unaffected",
                    "version": "6.1.191",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.6.*",
                    "status": "unaffected",
                    "version": "6.6.160",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.12.*",
                    "status": "unaffected",
                    "version": "6.12.113",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.18.*",
                    "status": "unaffected",
                    "version": "6.18.56",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "7.2.*",
                    "status": "unaffected",
                    "version": "7.2.10",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "7.3",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mctp: publish the mctp_dev only after it is initialised\n\nmctp_add_dev() links the new mctp_dev into dev-\u003emctp_ptr before mdev-\u003edev\nis assigned, so a reader that picks the device up in that window\ndereferences a net_device pointer that is still NULL:\n\nKASAN: null-ptr-deref in range [0x00000000000000b0-0x00000000000000b7]\nCall Trace:\n \u003cTASK\u003e\n ? __pfx_mctp_sendmsg (./include/linux/sockptr.h:49)\n ? __pfx_mctp_dst_output (net/mctp/route.c:41)\n ? selinux_socket_sendmsg (security/selinux/hooks.c:5278)\n ____sys_sendmsg (net/socket.c:775 (discriminator 1) net/socket.c:790\n (discriminator 1) net/socket.c:2684 (discriminator 1))\n ? __pfx_____sys_sendmsg (net/socket.c:1131)\n ? __pfx_copy_msghdr_from_user (net/socket.c:2590)\n ? update_cfs_rq_load_avg (kernel/sched/fair.c:5478)\n ___sys_sendmsg (net/socket.c:2738)\n ? __pfx____sys_sendmsg (net/socket.c:2625)\n ? perf_event_task_tick (./include/linux/rcupdate.h:838)\n ? sched_tick (kernel/sched/core.c:5818)\n ? clockevents_program_event (kernel/time/clockevents.c:372)\n ? fdget (./include/linux/rcupdate.h:873 fs/file.c:1100)\n __sys_sendmsg (net/socket.c:2770)\n ? __pfx___sys_sendmsg (net/socket.c:2751)\n do_syscall_64 (arch/x86/entry/syscall_64.c:63)\n entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)\n \u003c/TASK\u003e\n\nFix by publishing only once the object is fully initialised:\n__mctp_dev_get() runs under rcu_read_lock() only and hands\nthis object to readers as soon as mctp_ptr is assigned, so\nthey must never observe mdev-\u003edev == NULL."
          }
        ],
        "id": "CVE-2026-98812",
        "lastModified": "2026-10-30T13:21:28.907",
        "metrics": {},
        "published": "2026-10-18T16:17:35.313",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/288ef37e0c463192dbb6436e61cdc07ce666dcb9"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/58a270b5ecd8629114a4754d642bad6a33bef493"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/63120572edde85bb2b70b0ed4d4817ed52247613"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/aadf655e8ea9a8ffa24bb8d69f504572e8d18181"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/af6e4f931afc2d670d133aa2bedc8b6e3753c618"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/f37f42e6e039a48c2dcf6c079b9f7fbc864ab7ef"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/fdf09d0fa2fb639950bede185d22689f68df140e"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Received"
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-10-23T19:20:38+00:00",
      "cve": "CVE-2026-98812",
      "id": "CVE-2026-98812",
      "initial_release_date": "2026-10-18T00:00:00+00:00",
      "product_status:known_not_affected": "278",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: net/mctp: publish the mctp_dev only after it is initialised",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98812.json",
      "version": "3"
    }
  }
}



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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
Events included in the timeline

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    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.