CVE-2026-80631: Linux kernel · btrfs: lzo: reject compressed segment that overflows the compressed input
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.5 High · fixed in 7.0.0-1014.14~24.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 38% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 7.0.0-1014.14~24.04.1, 7.0.0-1017.17~24.04.1, 7.0.0-1016.16~24.04.1 +11
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 28 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.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| 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. The vendor advisory confirms that the issue has been resolved. Users should update to the fixed kernel releases to mitigate this vulnerability.
Description
A vulnerability in the Linux kernel's Btrfs filesystem compression code (lzo) allowed a crafted compressed segment to overflow the compressed input buffer, causing a null pointer dereference and kernel crash. This issue was fixed by rejecting any compressed segment that would extend beyond the compressed input size, treating it as corruption. The flaw affects specific Linux kernel versions listed and has a high severity rating with a CVSS score of 7.5.
References
- nvd.nist.gov/vuln/detail/CVE-2026-80631 (opens in a new tab)
- git.kernel.org/stable/c/1641d058adfbd50cf95d54581ed5d142ee82c07f (opens in a new tab)
- git.kernel.org/stable/c/b0d27d43791b7a3057c3c4aedf9b4aa033d37c46 (opens in a new tab)
- ubuntu.com/security/CVE-2026-80631 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-80631 (opens in a new tab)
- git.kernel.org/linus/b0d27d43791b7a3057c3c4aedf9b4aa033d37c46 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8889-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-3 (opens in a new tab)
- git.kernel.org/stable/c/1c48c8c807e49ac4f72819a89035fb8d2d094015 (opens in a new tab)
- git.kernel.org/stable/c/be7fb59512ffc2da5d98214a00117dfe9eccab78 (opens in a new tab)
- git.kernel.org/stable/c/d9b17f9ce67d00e48fab62dcae197612a58f625f (opens in a new tab)