VulnerabilityPublished 22 Aug 2026Updated 9 Oct 2026

CVE-2026-74671: Linux kernel · ima: fix out-of-bounds read in xattr_verify()

Affects Linux kernelSource GCVE Database

Not known to be exploited · fixed in 5.15.0-1117.124~20.04.1 : update Linux kernel when convenient.

Data as of 26 Oct 2026, 15:59 UTC

Severity

Medium

Rated by Threat Radar · CVSS not yet scored by NVD

EPSS: 0.1% chance of exploitation in 30 days – higher than 7% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 5.15.0-1117.124~20.04.1, 5.15.0-1123.132~20.04.1, 5.15.0-1122.131~20.04.1 +26

Exploitation evidence

Disclosed: evidence found.
CVE published 22 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
Ubuntu 26.04 LTSlinux`pkg:deb/ubuntu/linux?arch=source&distro=resolute`Other threats	Affected 6.17.0-5.5 – 7.0.0-38.38 23 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-aws`pkg:deb/ubuntu/linux-aws?arch=source&distro=resolute`Other threats	Affected 6.17.0-1002.2 – 7.0.0-1014.14 15 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-azure`pkg:deb/ubuntu/linux-azure?arch=source&distro=resolute`Other threats	Affected 6.17.0-1003.3 – 7.0.0-1017.17 15 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-azure-fde`pkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resolute`Other threats	Affected 7.0.0-1003.3 – 7.0.0-1016.16 9 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-gcp`pkg:deb/ubuntu/linux-gcp?arch=source&distro=resolute`Other threats	Affected 6.17.0-1002.2 – 7.0.0-1014.14 13 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-gke`pkg:deb/ubuntu/linux-gke?arch=source&distro=resolute`Other threats	Affected 7.0.0-1002.3 – 7.0.0-1008.9 6 affected builds	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

A patch is available and should be applied to affected Linux kernel versions to fix the out-of-bounds read in xattr_verify(). The vendor advisory from Ubuntu confirms that this issue has been addressed in updated kernel packages. Users should update their systems and reboot to apply the fix. No additional mitigations are indicated by the vendor advisory.

Description

A vulnerability in the Linux kernel's Integrity Measurement Architecture (IMA) subsystem was fixed to address an out-of-bounds read in the xattr_verify() function. The issue arises from a type mismatch in a digest-length check that causes an unsigned integer underflow, allowing a memcmp() operation to read beyond the allocated buffer. This flaw affects certain Linux kernel versions and could lead to memory safety issues. A patch is available to correct the comparison logic to prevent this out-of-bounds read.

Impact

This vulnerability can cause the kernel to read memory beyond the intended buffer boundaries, potentially leading to memory corruption or information disclosure. While no active exploits are known, the flaw could be leveraged by a local attacker to compromise system integrity or stability.

Summary

The Linux kernel vulnerability (CVE-2026-74671) involves an out-of-bounds read in the IMA subsystem's xattr_verify() function. The digest-length check mixes signed int and unsigned size_t types, causing an underflow when processing truncated extended attributes (xattr). Specifically, for a 1-byte IMA_XATTR_DIGEST_NG xattr, the arithmetic underflows and the check incorrectly passes, leading memcmp() to read bytes beyond the allocated buffer from vfs_getxattr_alloc(). The vulnerability exists because no upstream code clamps xattr_len to a safe range before the check. The fix rewrites the comparison to use only signed int operands, preventing implicit unsigned conversions and eliminating the out-of-bounds read.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 25 Oct 2026, 05:36 UTC

Technical details

References

Community reviews

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