CVE-2025-39964

In the Linux kernel, the following vulnerability has been resolved: crypto: af_alg - Disallow concurrent writes in af_alg_sendmsg Issuing two writes to the same af_alg socket is bogus as the data will be interleaved in an unpredictable fashion. Furthermore, concurrent writes may create inconsistencies in the internal socket state. Disallow this by adding a new ctx->write field that indiciates exclusive ownership for writing.

CVSS 3.1

5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS

1.6% chance of exploitation in the next 30 days; higher than 75% of CVEs (scores of 2026-10-25)

CISA KEV

listed 2026-09-18, due 2026-09-21

CWE

CWE-362

Published

2025-10-13

Modified

2026-10-19

Record from

the NVD, synced 2026-10-21

Affected

• linux:linux_kernel
• siemens:simatic_s7-1500_cpu_1518-4_pn\/dp_mfp_firmware
• siemens:simatic_s7-1500_cpu_1518f-4_pn\/dp_mfp_firmware

References

• https://git.kernel.org/stable/c/0f28c4adbc4a97437874c9b669fd7958a8c6d6ce
• https://git.kernel.org/stable/c/1b34cbbf4f011a121ef7b2d7d6e6920a036d5285
• https://git.kernel.org/stable/c/1f323a48e9b5ebfe6dc7d130fdf5c3c0e92a07c8
• https://git.kernel.org/stable/c/45bcf60fe49b37daab1acee57b27211ad1574042
• https://git.kernel.org/stable/c/7c4491b5644e3a3708f3dbd7591be0a570135b84

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