CVE-2026-93203: Linux kernel · batman-adv: bla: avoid CRC corruption due to parallel claim add
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.1 High.
Data as of 28 Oct 2026, 01:18 UTC
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:HExploitation evidence
Disclosed: evidence found.
CVE published 17 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.
What to do
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 fix is available that separates the claim addition and update logic to prevent concurrent CRC corruption. Users should apply the official patches or upgrade to fixed Linux kernel versions. Since this is a kernel vulnerability, updating the kernel to a patched version is the recommended remediation. No additional mitigation steps are indicated beyond applying the fix.
Description
A concurrency issue in the Linux kernel's batman-adv module caused CRC corruption due to parallel claim additions. This flaw occurs when multiple CPUs concurrently modify claim CRCs, leading to inconsistent CRC states that are not corrected by recomputation. The vulnerability affects specific Linux kernel versions and can result in integrity issues within the batman-adv backbone network claims.