VulnerabilityPublished 4 Sep 2026Updated 30 Sep 2026

CVE-2026-80912: Linux kernel · selinux: reject an unclaimed class value in security_get_classes()

Affects Linux kernelSource GCVE Database

Not known to be exploited.

Data as of 26 Oct 2026, 14:05 UTC

Severity

Medium

Rated by Threat Radar · CVSS not yet scored by NVD

EPSS: 0.1% chance of exploitation in 30 days – higher than 5% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

Exploitation evidence

Disclosed: evidence found.
CVE published 4 Sep 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.

ghsa-5v22-vqg5-vrr8

What to do

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 – 7.0.0-34.34 22 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 – 7.0.0-1013.13 14 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 – 7.0.0-1014.14 14 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 – 7.0.0-1013.13 8 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 – 7.0.0-1013.13 12 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 – 7.0.0-1007.8 5 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 fix has been applied to the Linux kernel to reject unclaimed class values in security_get_classes(), preventing NULL pointer dereferences. Users should update to a kernel version that includes this fix once available.

Description

In the Linux kernel, the following vulnerability has been resolved: selinux: reject an unclaimed class value in security_get_classes() security_get_classes() sizes an array by p_classes.nprim and fills it at value - 1, so a class value the policy never defines leaves a NULL. sel_make_classes() passes every entry to sel_make_dir(), reaching the same d_alloc_name() dereference as the permission array. The class symbol table is allowed to be sparse (policydb_class_isvalid() exists to absorb that), but this getter builds its own array straight from the hash table and has no such predicate. Fail the lookup when a value went unclaimed instead of handing out the NULL. Conforming policies define every class they declare and are unaffected.

Impact

The vulnerability could lead to NULL pointer dereferences in the SELinux kernel code when processing unclaimed class values, potentially causing kernel instability or crashes. However, SELinux policies that properly define all classes are not impacted. There is no indication of known exploits in the wild.

Summary

The vulnerability in the Linux kernel SELinux subsystem involved the security_get_classes() function, which sizes an array based on p_classes.nprim and fills it at value - 1. If a class value was not defined by the SELinux policy, this resulted in a NULL entry. The sel_make_classes() function then passed these entries to sel_make_dir(), which could dereference these NULL pointers in d_alloc_name(). The class symbol table is allowed to be sparse, but this function built its own array directly from the hash table without validating entries. The fix rejects unclaimed class values to prevent NULL pointer dereferences. Conforming SELinux policies that define every class are not affected.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 7 Sep 2026, 13:53 UTC

Technical details

References

Community reviews

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