{"cve_id":"CVE-2025-39964","published":"2025-10-13T14:15:34.737000+00:00","last_modified":"2026-10-19T21:10:00.160000+00:00","vuln_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_version":"3.1","cvss_vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","base_score":5.5,"base_severity":"MEDIUM","attack_vector":"LOCAL","privileges_req":"LOW","user_interaction":"NONE","scope":"UNCHANGED","impact_c":"NONE","impact_i":"NONE","impact_a":"HIGH","cwe_ids":["CWE-362"],"in_kev":true,"kev_date_added":"2026-09-18","kev_ransomware":false,"epss_score":0.0157,"epss_percentile":0.75375,"cap_rule_version":"0.1.1","stage":"PRIV_ESC","req_access":"USER","req_vector":"LOCAL","req_user_interaction":false,"grant_access":"PRIV","caps":["CODE_EXEC","DOS","PRIV_GAIN"],"terminal":false,"cap_confidence":"high","ingested_at":"2026-10-28T03:23:10.914582+00:00","first_seen":"2025-10-13T14:15:34.737000+00:00","kev_first_seen":"2026-09-22T06:44:39.254185+00:00","novelty_score":0.0,"novelty_reasons":[],"novelty_at":"2026-10-02T03:22:09.438791+00:00","vendors":["linux","siemens"],"products":["linux_kernel","simatic_s7-1500_cpu_1518-4_pn\\/dp_mfp","simatic_s7-1500_cpu_1518-4_pn\\/dp_mfp_firmware","simatic_s7-1500_cpu_1518f-4_pn\\/dp_mfp","simatic_s7-1500_cpu_1518f-4_pn\\/dp_mfp_firmware"],"affected":[{"vendor":"linux","product":"linux_kernel","ranges":["≥ 2.6.38 and < 5.10.245","≥ 5.11 and < 5.15.194","≥ 5.16 and < 6.1.154","≥ 6.2 and < 6.6.108","≥ 6.7 and < 6.12.49","≥ 6.13 and < 6.16.9","6.17"]},{"vendor":"siemens","product":"simatic_s7-1500_cpu_1518-4_pn\\/dp_mfp_firmware","ranges":["≥ 3.1.6"]},{"vendor":"siemens","product":"simatic_s7-1500_cpu_1518f-4_pn\\/dp_mfp_firmware","ranges":["≥ 3.1.6"]}]}