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

FKIE_CVE-2026-74400

Vulnerability from fkie_nvd - Published: 2026-08-15 06:22 - Updated: 2026-08-17 06:19
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: bpf: fix crash in bpf_[set|remove]_dentry_xattr for negative dentries bpf_set_dentry_xattr and bpf_remove_dentry_xattr BPF kfuncs attempt to lock the inode of the supplied dentry without checking if it is NULL. If a negative dentry is passed (e.g. from security_inode_create), d_inode(dentry) returns NULL, and inode_lock(inode) will cause a NULL pointer dereference. Trivially fix this by adding a NULL check for inode before attempting to lock it, returning -EINVAL if it is NULL. Additionally, drop WARN_ON(!inode) in bpf_xattr_read_permission() and bpf_xattr_write_permission(). These warnings could be triggered by passing a negative dentry to bpf_get_dentry_xattr() or the _locked variants of the xattr kfuncs, potentially causing a Denial of Service on systems with panic_on_warn enabled. Instead, simply return -EINVAL.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/0160edf2af51c5fde742973742c5d10497901b21
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/07410646f6ff1d23222f105ccab778957d401bbe
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/e003f3a4be738f650e283e92d07017c3fef8da52
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/bpf_fs_kfuncs.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "e003f3a4be738f650e283e92d07017c3fef8da52",
              "status": "affected",
              "version": "56467292794b800164df20c076c409ac548e56ec",
              "versionType": "git"
            },
            {
              "lessThan": "0160edf2af51c5fde742973742c5d10497901b21",
              "status": "affected",
              "version": "56467292794b800164df20c076c409ac548e56ec",
              "versionType": "git"
            },
            {
              "lessThan": "07410646f6ff1d23222f105ccab778957d401bbe",
              "status": "affected",
              "version": "56467292794b800164df20c076c409ac548e56ec",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/bpf_fs_kfuncs.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.15"
            },
            {
              "lessThan": "6.15",
              "status": "unaffected",
              "version": "0",
              "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"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: fix crash in bpf_[set|remove]_dentry_xattr for negative dentries\n\nbpf_set_dentry_xattr and bpf_remove_dentry_xattr BPF kfuncs attempt to\nlock the inode of the supplied dentry without checking if it is\nNULL. If a negative dentry is passed (e.g. from\nsecurity_inode_create), d_inode(dentry) returns NULL, and\ninode_lock(inode) will cause a NULL pointer dereference.\n\nTrivially fix this by adding a NULL check for inode before attempting\nto lock it, returning -EINVAL if it is NULL.\n\nAdditionally, drop WARN_ON(!inode) in bpf_xattr_read_permission() and\nbpf_xattr_write_permission(). These warnings could be triggered by\npassing a negative dentry to bpf_get_dentry_xattr() or the _locked\nvariants of the xattr kfuncs, potentially causing a Denial of Service\non systems with panic_on_warn enabled. Instead, simply return -EINVAL."
    }
  ],
  "id": "CVE-2026-74400",
  "lastModified": "2026-08-17T06:19:35.183",
  "metrics": {},
  "published": "2026-08-15T06:22:42.030",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/0160edf2af51c5fde742973742c5d10497901b21"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/07410646f6ff1d23222f105ccab778957d401bbe"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/e003f3a4be738f650e283e92d07017c3fef8da52"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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.