{"cve":"CVE-2025-39964","nvd":{"published":"2025-10-13T14:15:34.737","modified":"2026-10-19T21:10:00.160","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: af_alg - Disallow concurrent writes in af_alg_sendmsg\n\nIssuing two writes to the same af_alg socket is bogus as the\ndata will be interleaved in an unpredictable fashion.  Furthermore,\nconcurrent writes may create inconsistencies in the internal\nsocket state.\n\nDisallow this by adding a new ctx->write field that indiciates\nexclusive ownership for writing.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-362"],"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"],"products":["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"],"source":"nvd","synced_at":"2026-10-21T03:43:09.190223697+00:00"},"epss":{"cve":"CVE-2025-39964","score":0.0157,"percentile":0.75193,"date":"2026-10-25"},"kev":{"cve":"CVE-2025-39964","date_added":"2026-09-18","due_date":"2026-09-21","vendor":"Linux","product":"Kernel","known_ransomware":false},"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}