GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

CVE-2026-74359 (GCVE-0-2026-74359)

Vulnerability from cvelistv5 – Published: 2026-08-15 05:58 – Updated: 2026-08-17 05:46
VLAI
Title
configfs_lookup(): don't leave ->s_dentry dangling on failure
Summary
In the Linux kernel, the following vulnerability has been resolved: configfs_lookup(): don't leave ->s_dentry dangling on failure Normally ->s_dentry is cleared when dentry it's pointing to becomes negative (on eviction, realistically). However, that only happens if dentry gets to be positive in the first place; in case of inode allocation failure dentry never becomes positive, so ->d_iput() is not called at all. We do part of what normally would've been done by configfs_d_iput() (dropping the reference to configfs_dirent) manually, but we do not clear ->s_dentry there. Sloppy as it is, it does not matter in case of configfs_create_{dir,link}() - there configfs_dirent does not survive dropping the sole reference to it. However, for configfs_lookup() it *does* survive, with a dangling pointer to soon to be freed dentry sitting it its ->s_dentry. Subsequent getdents(2) in that directory will end up dereferencing that pointer in order to pick the inode number. Use after free... This is the minimal fix; the right approach is to set the linkage between dentry and configfs_dirent only after we know that we have an inode, but that takes more surgery and the bug had been there since 2006, so...
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 3d0f89bb169482d26d5aa4e82e763077e7e9bc4d , < 3e83b2203aa59bd279e4f677ec793d49dc9d019e (git)
Affected: 3d0f89bb169482d26d5aa4e82e763077e7e9bc4d , < b6e9c82522ddaa3ac0706b295ff4a71975d4f883 (git)
Affected: 3d0f89bb169482d26d5aa4e82e763077e7e9bc4d , < eee07d769da5ac4e4f7bd0bc17828646a318d499 (git)
Affected: 3d0f89bb169482d26d5aa4e82e763077e7e9bc4d , < 9c747dcee164ead300de90550ad9e4122f0d1bbb (git)
Affected: 3d0f89bb169482d26d5aa4e82e763077e7e9bc4d , < c3b073a209a9baa691b744318ac929fecdd8847c (git)
Affected: 3d0f89bb169482d26d5aa4e82e763077e7e9bc4d , < 57088b06109f3222963c639d8d743f42c2899b13 (git)
Affected: 3d0f89bb169482d26d5aa4e82e763077e7e9bc4d , < 10da12d352b7b2bb330a8609fdda9a58bf0e9856 (git)
guessed Create a notification for this product.
Linux Linux Affected: 2.6.16
Unaffected: 0 , < 2.6.16 (semver)
Unaffected: 5.15.212 , ≤ 5.15.* (semver)
Unaffected: 6.1.178 , ≤ 6.1.* (semver)
Unaffected: 6.6.145 , ≤ 6.6.* (semver)
Unaffected: 6.12.97 , ≤ 6.12.* (semver)
Unaffected: 6.18.40 , ≤ 6.18.* (semver)
Unaffected: 7.1.5 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/configfs/dir.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "3e83b2203aa59bd279e4f677ec793d49dc9d019e",
              "status": "affected",
              "version": "3d0f89bb169482d26d5aa4e82e763077e7e9bc4d",
              "versionType": "git"
            },
            {
              "lessThan": "b6e9c82522ddaa3ac0706b295ff4a71975d4f883",
              "status": "affected",
              "version": "3d0f89bb169482d26d5aa4e82e763077e7e9bc4d",
              "versionType": "git"
            },
            {
              "lessThan": "eee07d769da5ac4e4f7bd0bc17828646a318d499",
              "status": "affected",
              "version": "3d0f89bb169482d26d5aa4e82e763077e7e9bc4d",
              "versionType": "git"
            },
            {
              "lessThan": "9c747dcee164ead300de90550ad9e4122f0d1bbb",
              "status": "affected",
              "version": "3d0f89bb169482d26d5aa4e82e763077e7e9bc4d",
              "versionType": "git"
            },
            {
              "lessThan": "c3b073a209a9baa691b744318ac929fecdd8847c",
              "status": "affected",
              "version": "3d0f89bb169482d26d5aa4e82e763077e7e9bc4d",
              "versionType": "git"
            },
            {
              "lessThan": "57088b06109f3222963c639d8d743f42c2899b13",
              "status": "affected",
              "version": "3d0f89bb169482d26d5aa4e82e763077e7e9bc4d",
              "versionType": "git"
            },
            {
              "lessThan": "10da12d352b7b2bb330a8609fdda9a58bf0e9856",
              "status": "affected",
              "version": "3d0f89bb169482d26d5aa4e82e763077e7e9bc4d",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/configfs/dir.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.16"
            },
            {
              "lessThan": "2.6.16",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.212",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.178",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.145",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.97",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.212",
                  "versionStartIncluding": "2.6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.178",
                  "versionStartIncluding": "2.6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.145",
                  "versionStartIncluding": "2.6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.97",
                  "versionStartIncluding": "2.6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.40",
                  "versionStartIncluding": "2.6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.5",
                  "versionStartIncluding": "2.6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "2.6.16",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nconfigfs_lookup(): don\u0027t leave -\u003es_dentry dangling on failure\n\nNormally -\u003es_dentry is cleared when dentry it\u0027s pointing to becomes\nnegative (on eviction, realistically).  However, that only happens\nif dentry gets to be positive in the first place; in case of inode\nallocation failure dentry never becomes positive, so -\u003ed_iput()\nis not called at all.\n\nWe do part of what normally would\u0027ve been done by configfs_d_iput()\n(dropping the reference to configfs_dirent) manually, but we do\nnot clear -\u003es_dentry there.  Sloppy as it is, it does not matter in\ncase of configfs_create_{dir,link}() - there configfs_dirent does\nnot survive dropping the sole reference to it.\n\nHowever, for configfs_lookup() it *does* survive, with a dangling\npointer to soon to be freed dentry sitting it its -\u003es_dentry.\n\nSubsequent getdents(2) in that directory will end up dereferencing\nthat pointer in order to pick the inode number.  Use after free...\n\nThis is the minimal fix; the right approach is to set the linkage\nbetween dentry and configfs_dirent only after we know that we have\nan inode, but that takes more surgery and the bug had been there\nsince 2006, so..."
        }
      ],
      "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 bug is reached only via local VFS syscalls (openat/stat on a configfs attribute and getdents on its parent) against /sys/kernel/config; configfs is not exposed through network-facing kernel services such as ksmbd, nfsd, or the TCP/IP stack.\nAC:L - Exploitation is a deterministic error-path bug, not a race: inode allocation failure in configfs_lookup() leaves sd-\u003es_dentry dangling and a follow-up getdents reliably dereferences it; the attacker can force ENOMEM by applying memory pressure they control.\nPR:L - Default configfs modes (0755 directories, 0644 attributes) let any local user read/list kernel-registered subsystem trees (e.g. nvmet, usb_gadget) without init-namespace root; mkdir/write still need admin, but triggering lookup on existing unpinned attributes does not.\nUI:N - No victim interaction is required beyond the attacker issuing their own syscalls on configfs paths; configfs is mounted at boot under /sys/kernel/config and exploitation does not depend on another user mounting or opening files.\nS:U - The use-after-free corrupts kernel heap memory and enables local privilege escalation within the same kernel security domain; it does not cross VM, IOMMU, or sandbox boundaries.\nC:H - configfs_readdir() reads d_inode() through a dangling sd-\u003es_dentry after failed lookup, giving a slab use-after-free read primitive on freed dentry/inode memory that can disclose kernel data or pointers via heap reuse.\nI:H - Reclaimed dentry/inode slabs let an attacker shape freed-object contents and convert the dangling pointer into arbitrary kernel writes and control-flow hijack, consistent with standard UAF exploitation of VFS objects.\nA:H - Dereferencing the freed dentry during getdents causes kernel oops/panic (as described in the fix); the UAF is repeatable and can deny service even when full exploitation is not attempted."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:46:19.411Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/3e83b2203aa59bd279e4f677ec793d49dc9d019e"
        },
        {
          "url": "https://git.kernel.org/stable/c/b6e9c82522ddaa3ac0706b295ff4a71975d4f883"
        },
        {
          "url": "https://git.kernel.org/stable/c/eee07d769da5ac4e4f7bd0bc17828646a318d499"
        },
        {
          "url": "https://git.kernel.org/stable/c/9c747dcee164ead300de90550ad9e4122f0d1bbb"
        },
        {
          "url": "https://git.kernel.org/stable/c/c3b073a209a9baa691b744318ac929fecdd8847c"
        },
        {
          "url": "https://git.kernel.org/stable/c/57088b06109f3222963c639d8d743f42c2899b13"
        },
        {
          "url": "https://git.kernel.org/stable/c/10da12d352b7b2bb330a8609fdda9a58bf0e9856"
        }
      ],
      "title": "configfs_lookup(): don\u0027t leave -\u003es_dentry dangling on failure",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-74359",
    "datePublished": "2026-08-15T05:58:43.456Z",
    "dateReserved": "2026-08-15T05:44:03.887Z",
    "dateUpdated": "2026-08-17T05:46:19.411Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-74359",
      "date": "2026-09-04",
      "epss": "0.00126",
      "percentile": "0.02533"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-74359\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-08-15T06:22:37.430\",\"lastModified\":\"2026-08-17T06:19:30.627\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nconfigfs_lookup(): don\u0027t leave -\u003es_dentry dangling on failure\\n\\nNormally -\u003es_dentry is cleared when dentry it\u0027s pointing to becomes\\nnegative (on eviction, realistically).  However, that only happens\\nif dentry gets to be positive in the first place; in case of inode\\nallocation failure dentry never becomes positive, so -\u003ed_iput()\\nis not called at all.\\n\\nWe do part of what normally would\u0027ve been done by configfs_d_iput()\\n(dropping the reference to configfs_dirent) manually, but we do\\nnot clear -\u003es_dentry there.  Sloppy as it is, it does not matter in\\ncase of configfs_create_{dir,link}() - there configfs_dirent does\\nnot survive dropping the sole reference to it.\\n\\nHowever, for configfs_lookup() it *does* survive, with a dangling\\npointer to soon to be freed dentry sitting it its -\u003es_dentry.\\n\\nSubsequent getdents(2) in that directory will end up dereferencing\\nthat pointer in order to pick the inode number.  Use after free...\\n\\nThis is the minimal fix; the right approach is to set the linkage\\nbetween dentry and configfs_dirent only after we know that we have\\nan inode, but that takes more surgery and the bug had been there\\nsince 2006, so...\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"fs/configfs/dir.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"3d0f89bb169482d26d5aa4e82e763077e7e9bc4d\",\"lessThan\":\"3e83b2203aa59bd279e4f677ec793d49dc9d019e\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3d0f89bb169482d26d5aa4e82e763077e7e9bc4d\",\"lessThan\":\"b6e9c82522ddaa3ac0706b295ff4a71975d4f883\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3d0f89bb169482d26d5aa4e82e763077e7e9bc4d\",\"lessThan\":\"eee07d769da5ac4e4f7bd0bc17828646a318d499\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3d0f89bb169482d26d5aa4e82e763077e7e9bc4d\",\"lessThan\":\"9c747dcee164ead300de90550ad9e4122f0d1bbb\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3d0f89bb169482d26d5aa4e82e763077e7e9bc4d\",\"lessThan\":\"c3b073a209a9baa691b744318ac929fecdd8847c\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3d0f89bb169482d26d5aa4e82e763077e7e9bc4d\",\"lessThan\":\"57088b06109f3222963c639d8d743f42c2899b13\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3d0f89bb169482d26d5aa4e82e763077e7e9bc4d\",\"lessThan\":\"10da12d352b7b2bb330a8609fdda9a58bf0e9856\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"fs/configfs/dir.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"2.6.16\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"2.6.16\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.212\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.178\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.145\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.97\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.40\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.5\",\"lessThanOrEqual\":\"7.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.2\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.8,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.9}]},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/10da12d352b7b2bb330a8609fdda9a58bf0e9856\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/3e83b2203aa59bd279e4f677ec793d49dc9d019e\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/57088b06109f3222963c639d8d743f42c2899b13\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/9c747dcee164ead300de90550ad9e4122f0d1bbb\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/b6e9c82522ddaa3ac0706b295ff4a71975d4f883\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/c3b073a209a9baa691b744318ac929fecdd8847c\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/eee07d769da5ac4e4f7bd0bc17828646a318d499\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Important",
      "current_release_date": "2026-08-20T20:34:14+00:00",
      "cve": "CVE-2026-74359",
      "id": "CVE-2026-74359",
      "initial_release_date": "2026-08-15T00:00:00+00:00",
      "product_status:known_affected": "260",
      "product_status:under_investigation": "14",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: configfs_lookup(): don\u0027t leave -\u003es_dentry dangling on failure",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74359.json",
      "version": "3"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





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.


Detection rules are retrieved from Rulezet.