CVE-2026-23095: Linux kernel · gue: Fix skb memleak with inner IP protocol 0.
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.5 High · fixed in 5.15.0-1105.112~20.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 22% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1105.112~20.04.1, 5.15.0-1110.119~20.04.1, 5.15.0-1106.115~20.04.1 +59
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 4 Feb 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 25.10linuxpkg:deb/ubuntu/linux@6.17.0-40.40?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws@6.17.0-1019.19?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure@6.17.0-1020.20?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde@6.17.0-1017.17?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-gcppkg:deb/ubuntu/linux-gcp@6.17.0-1020.22?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-oraclepkg:deb/ubuntu/linux-oracle@6.17.0-1018.18?arch=source&distro=questingOther 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-aws kernel versions. The vendor advisory confirms the issue is fixed in updated kernel releases. Users should update their systems to the patched kernel versions to remediate this vulnerability. No additional mitigation steps are required beyond applying the official fix.
Description
A memory leak vulnerability in the Linux kernel's GUE (Generic UDP Encapsulation) implementation was fixed. The issue involved skb (socket buffer) memory leaking when processing packets with an inner IP protocol number of 0. This flaw was reported by syzbot and addressed by dropping such packets to prevent the leak. The vulnerability affects specific linux-aws kernel versions and has a CVSS score of 7.5, indicating a medium severity impact primarily on availability.
References
- ubuntu.com/security/CVE-2026-23095 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-23095 (opens in a new tab)
- git.kernel.org/linus/9a56796ad258786d3624eef5aefba394fc9bdded (opens in a new tab)
- git.kernel.org/stable/c/5437a279804ced8088cabb945dba88a26d828f8c (opens in a new tab)
- git.kernel.org/stable/c/9a56796ad258786d3624eef5aefba394fc9bdded (opens in a new tab)
- git.kernel.org/stable/c/ce569b389a5c78d64788a5ea94560e17fa574b35 (opens in a new tab)
- git.kernel.org/stable/c/f87b9b7a618c82e7465e872eb10e14c803871892 (opens in a new tab)
- ubuntu.com/security/notices/USN-8162-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8180-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8180-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8186-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8187-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8188-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8180-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8180-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8180-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-8243-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8180-6 (opens in a new tab)
- ubuntu.com/security/notices/USN-8275-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8278-1 (opens in a new tab)