CVE-2025-39964 KEV
7.8
HIGH · CVSS 3.1 · EPSS 1% (pctl 61)
Patch first
On CISA KEV — known exploited in the wild, due 2026-09-21.
Description
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.
Scoring
| CVSS | 7.8 (HIGH, v3.1) |
|---|---|
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| EPSS | 1% — more likely to be exploited than 61% of all CVEs |
| Weakness | CWE-362 |
| On CISA KEV | yes — remediate by 2026-09-21 |
| Public exploit | none known |
| Published | 2025-10-13 |
| Last modified | 2026-09-19 |
CISA KEV
| Name | Linux Kernel Race Condition Vulnerability |
|---|---|
| Added | 2026-09-18 |
| Due | 2026-09-21 |
| Vendor / product | Linux / Kernel |
| Ransomware use | none reported |
Affected (5)
| Vendor | Product |
|---|---|
| linux | linux kernel |
| siemens | simatic s7-1500 cpu 1518-4 pn\/dp mfp |
| siemens | simatic s7-1500 cpu 1518-4 pn\/dp mfp firmware |
| siemens | simatic s7-1500 cpu 1518f-4 pn\/dp mfp |
| 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
- https://git.kernel.org/stable/c/9aee87da5572b3a14075f501752e209801160d3d
- https://git.kernel.org/stable/c/e4c1ec11132ec466f7362a95f36a506ce4dc08c9
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-39964
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