CVE-2025-39931: Linux Kernel

Medium severity, CVSS 5.5. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: crypto: af_alg - Set merge to zero early in af_alg_sendmsg If an error causes af_alg_sendmsg to abort, ctx->merge may contain a garbage value from the previous loop. This may then trigger a crash on the next entry into af_alg_sendmsg when it attempts to do a merge that can't be done. Fix this by setting ctx->merge to zero near the start of the loop.

Affected products

• Linux Linux Kernel: from 2.6.38, before 6.1.154 (fixed in 6.1.154); from 6.2, before 6.6.108 (fixed in 6.6.108); from 6.7, before 6.12.49 (fixed in 6.12.49); from 6.13, before 6.16.9 (fixed in 6.16.9); version 6.17 only

Published 2025-10-04. Last modified 2026-07-30.