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CVE-2026-74359 Linux CVE debrief

A use-after-free vulnerability exists in the Linux kernel's configfs_lookup() function. When an inode allocation fails, the dentry is not cleared, leading to a dangling pointer that can cause a crash or potentially allow an attacker to execute arbitrary code if they can trigger the specific conditions. The vulnerability affects Linux kernel deployments and requires immediate attention from Linux kernel developers, maintainers, and users of Linux-based systems to ensure their systems are updated with the fix.

Vendor
Linux
Product
Unknown
CVSS
HIGH 7.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-08-15
Original CVE updated
2026-10-16
Advisory published
2026-08-15
Advisory updated
2026-10-16

Who should care

Linux kernel developers and maintainers, Linux distribution maintainers, and users of Linux-based systems should be aware of this vulnerability and take steps to ensure their systems are updated with the fix.

Why it matters

This vulnerability in the Linux kernel's configfs_lookup() function can lead to a denial of service or potentially allow an attacker to execute arbitrary code. Linux kernel developers, maintainers, and users should be aware of this vulnerability and take steps to ensure their systems are updated with the fix.

  • Denial of service due to system crashes
  • Potential code execution with elevated privileges
  • Increased risk of privilege escalation
  • Need for verification of system exposure and patch application

Technical summary

The configfs_lookup() function in the Linux kernel does not properly handle inode allocation failures, leading to a use-after-free vulnerability. An attacker may be able to exploit this vulnerability to cause a denial of service or potentially execute arbitrary code. The vulnerability affects Linux kernel deployments and requires immediate attention from Linux kernel developers, maintainers, and users of Linux-based systems to ensure their systems are updated with the fix. The fix involves updating the Linux kernel to a version that includes the patch for the configfs_lookup() function.

Defensive priority

High

Recommended defensive actions

  • Review and apply the patches provided by the Linux kernel maintainers to address the vulnerability.
  • Ensure that the Linux kernel is updated to a version that includes the fix.
  • Monitor systems for potential exploitation attempts.
  • Review compensating controls for exposed systems while remediation is scheduled and verified.
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review.
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented.
  • Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.

Evidence notes

The CVE record and source item provide details about the vulnerability, including a description of the issue and references to the relevant commits that address the problem. The configfs_lookup() function in the Linux kernel does not properly handle inode allocation failures, leading to a use-after-free vulnerability. The vulnerability has been resolved in the Linux kernel, and patches are available to address the issue. Defenders should verify system exposure and apply the patches provided by the Linux kernel maintainers.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-74359 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-74359

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-74359 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-74359

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • configfs_lookup(): don't leave ->s_dentry dangling on failure

    Unverified legacy reference

    URL: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/74xxx/CVE-2026-74359.json

    cve_program_cvelist_v5

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/3e83b2203aa59bd279e4f677ec793d49dc9d019e

    Supplemental source

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/b6e9c82522ddaa3ac0706b295ff4a71975d4f883

    Supplemental source

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/eee07d769da5ac4e4f7bd0bc17828646a318d499

    Supplemental source

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/9c747dcee164ead300de90550ad9e4122f0d1bbb

    Supplemental source

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/c3b073a209a9baa691b744318ac929fecdd8847c

    Supplemental source

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/57088b06109f3222963c639d8d743f42c2899b13

    Supplemental source

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/10da12d352b7b2bb330a8609fdda9a58bf0e9856

    Supplemental source

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.