CVE-2026-52914

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux610bfc6bc99bc83680d190ebc69359a05fc7f605 < e4f3f6b818aa6a678bc54a2d4e0bece2303c6a64affected
LinuxLinux610bfc6bc99bc83680d190ebc69359a05fc7f605 < 37be61825b15534a16ff9cfc9546de155b6df982affected
LinuxLinux610bfc6bc99bc83680d190ebc69359a05fc7f605 < 975563c5de1123dde1ec7946bf5556d20c89d74eaffected
LinuxLinux610bfc6bc99bc83680d190ebc69359a05fc7f605 < f653b040dad1af70fa5cd4fe085e4758925480c9affected
LinuxLinux610bfc6bc99bc83680d190ebc69359a05fc7f605 < e910dbf509125fe51ad68e4fa74dc8ab0a8e787aaffected
LinuxLinux610bfc6bc99bc83680d190ebc69359a05fc7f605 < 3eb8bcb823391bd58997831b3c9c152a4ba8e255affected
LinuxLinux610bfc6bc99bc83680d190ebc69359a05fc7f605 < fdb2c96efb2baeb3725e9ce3ede8f1e36f5490f0affected
LinuxLinux610bfc6bc99bc83680d190ebc69359a05fc7f605 < 9cd3f16c320bfdadd4509358122368deb56a5741affected
LinuxLinux3.13affected
LinuxLinux0 < 3.13unaffected
LinuxLinux5.10.258 <= 5.10.*unaffected
LinuxLinux5.15.209 <= 5.15.*unaffected
LinuxLinux6.1.175 <= 6.1.*unaffected
LinuxLinux6.6.142 <= 6.6.*unaffected
LinuxLinux6.12.92 <= 6.12.*unaffected
LinuxLinux6.18.34 <= 6.18.*unaffected
LinuxLinux7.0.11 <= 7.0.*unaffected
LinuxLinux7.1 <= *unaffected

Weaknesses

References