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 26 Oct 2026, 13:47 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 26% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
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 for this vulnerability is available and has been applied in the affected Linux kernel versions. Users should update to the patched versions listed to resolve the CRC corruption issue in batman-adv. Since the vulnerability is in the Linux kernel, applying official kernel updates from the vendor or distribution is the recommended remediation.
Description
A vulnerability in the Linux kernel's batman-adv module related to CRC corruption in backbone claim handling has been resolved. The issue arises from parallel processing of claim additions and backbone changes, causing incorrect CRC calculations. This can lead to invalid CRC values for claims associated with different gateways. The fix involves separating the logic for new claim additions and updates to existing claims to ensure CRC integrity.
References
- nvd.nist.gov/vuln/detail/CVE-2026-93203 (opens in a new tab)
- git.kernel.org/stable/c/08645ab95768b88e2ff85a89211994651710465b (opens in a new tab)
- git.kernel.org/stable/c/1d390db003cbb52cdd86837608bff3794501a5ea (opens in a new tab)
- git.kernel.org/stable/c/3d4a9ae2c69c0fe4c3c69587288241243bb7a39b (opens in a new tab)
- git.kernel.org/stable/c/8bcfa58c4277bff1882a23547c37ab08aa1de12f (opens in a new tab)
- git.kernel.org/stable/c/a3e07db74f22a85aeeb51c600da5c98b9cbca11f (opens in a new tab)
- git.kernel.org/stable/c/ad982d925f00d860d2467811256ffadcccd9e4a7 (opens in a new tab)
- git.kernel.org/stable/c/d5b0e7574da5a485f4dbec32a15911900a4487c2 (opens in a new tab)
- git.kernel.org/stable/c/e54602d9e38db8573f2097d60c7ea8be0a5af1fa (opens in a new tab)
- ubuntu.com/security/CVE-2026-93203 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-93203 (opens in a new tab)
- git.kernel.org/linus/08645ab95768b88e2ff85a89211994651710465b (opens in a new tab)