CVE-2026-52914

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.

CVSS v3.1 Score

9.8

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0052

Probability of exploitation

0.40%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://git.kernel.org/stable/c/37be61825b15534a16ff9cfc9546de155b6df982 https://git.kernel.org/stable/c/3eb8bcb823391bd58997831b3c9c152a4ba8e255 https://git.kernel.org/stable/c/975563c5de1123dde1ec7946bf5556d20c89d74e https://git.kernel.org/stable/c/9cd3f16c320bfdadd4509358122368deb56a5741 https://git.kernel.org/stable/c/e4f3f6b818aa6a678bc54a2d4e0bece2303c6a64 https://git.kernel.org/stable/c/e910dbf509125fe51ad68e4fa74dc8ab0a8e787a https://git.kernel.org/stable/c/f653b040dad1af70fa5cd4fe085e4758925480c9 https://git.kernel.org/stable/c/fdb2c96efb2baeb3725e9ce3ede8f1e36f5490f0

Frequently Asked Questions

What is CVE-2026-52914? +

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. It has a CVSS v3.1 base score of 9.8 (CRITICAL).

How severe is CVE-2026-52914? +

CVE-2026-52914 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately. The EPSS score is 0.0052, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-52914? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.