CVE-2026-52914: Linux kernel · batman-adv: fix fragment reassembly length accounting
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 9.8 Critical · fixed in 3.13.0-217.268 : patch Linux kernel as a priority.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 49% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 3.13.0-217.268, 4.4.0-1158.164, 4.15.0-1206.221~14.04.1 +125
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 24 Jun 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.
Description
In the Linux kernel, the following vulnerability has been resolved: batman-adv: fix fragment reassembly length accounting batman-adv keeps a running payload length for queued fragments and uses it to validate a fragment chain before reassembly. That accounting currently allows the accumulated fragment length to be truncated during updates. As a result, malformed fragment chains can bypass the intended validation and drive reassembly with inconsistent length state, leading to a local denial of service. Fix the accounting by storing the accumulated length in a length-typed field and rejecting update overflows before the existing validation logic runs. The fix was verified against the original reproducer and against valid fragment reassembly paths.
References
- ubuntu.com/security/CVE-2026-52914 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-52914 (opens in a new tab)
- git.kernel.org/linus/9cd3f16c320bfdadd4509358122368deb56a5741 (opens in a new tab)
- git.kernel.org/stable/c/37be61825b15534a16ff9cfc9546de155b6df982 (opens in a new tab)
- git.kernel.org/stable/c/3eb8bcb823391bd58997831b3c9c152a4ba8e255 (opens in a new tab)
- git.kernel.org/stable/c/975563c5de1123dde1ec7946bf5556d20c89d74e (opens in a new tab)
- git.kernel.org/stable/c/9cd3f16c320bfdadd4509358122368deb56a5741 (opens in a new tab)
- git.kernel.org/stable/c/e4f3f6b818aa6a678bc54a2d4e0bece2303c6a64 (opens in a new tab)
- git.kernel.org/stable/c/e910dbf509125fe51ad68e4fa74dc8ab0a8e787a (opens in a new tab)
- git.kernel.org/stable/c/f653b040dad1af70fa5cd4fe085e4758925480c9 (opens in a new tab)
- git.kernel.org/stable/c/fdb2c96efb2baeb3725e9ce3ede8f1e36f5490f0 (opens in a new tab)
- ubuntu.com/security/notices/USN-8566-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8568-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8569-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8575-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8576-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8593-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8575-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8576-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8603-1 (opens in a new tab)