{"id":"CVE-2025-21955","title":"ksmbd: prevent connection release during oplock break notification","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: prevent connection release during oplock break notification\n\nksmbd_work could be freed when after connection release.\nIncrement r_count of ksmbd_conn to indicate…","severity":"high","cvss":8.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 0626e6641f6b467447c81dd7678a69c66f7746cf < 8e6508c7ecb1802909f294827eff38f301d0c937","Linux >= 0626e6641f6b467447c81dd7678a69c66f7746cf < 09aeab68033161cb54f194da93e51a11aee6144b","Linux >= 0626e6641f6b467447c81dd7678a69c66f7746cf < a4261bbc33fbf99b99c80aa3a2c5097611802980","Linux >= 0626e6641f6b467447c81dd7678a69c66f7746cf < f17d1c63a76b0fe8e9c78023a86507a3a6d62cfa","Linux >= 0626e6641f6b467447c81dd7678a69c66f7746cf < 3aa660c059240e0c795217182cf7df32909dd917","Linux 5.15"],"published":"2025-04-01","updated":"2026-10-30","sourceUpdated":"2026-10-30T12:21:02.884Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2025-21955","references":[{"url":"https://git.kernel.org/stable/c/8e6508c7ecb1802909f294827eff38f301d0c937"},{"url":"https://git.kernel.org/stable/c/09aeab68033161cb54f194da93e51a11aee6144b"},{"url":"https://git.kernel.org/stable/c/a4261bbc33fbf99b99c80aa3a2c5097611802980"},{"url":"https://git.kernel.org/stable/c/f17d1c63a76b0fe8e9c78023a86507a3a6d62cfa"},{"url":"https://git.kernel.org/stable/c/3aa660c059240e0c795217182cf7df32909dd917"}],"tags":["cve.org"],"epss":0.00502,"epssPercentile":0.43249,"ingestedAt":"2026-11-03T15:48:07.702Z","slug":"CVE-2025-21955","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: prevent connection release during oplock break notification\n\nksmbd_work could be freed when after connection release.\nIncrement r_count of ksmbd_conn to indicate that requests\nare not finished yet and to not release the connection.\n\n## Affected\n\n- `Linux >= 0626e6641f6b467447c81dd7678a69c66f7746cf < 8e6508c7ecb1802909f294827eff38f301d0c937`\n- `Linux >= 0626e6641f6b467447c81dd7678a69c66f7746cf < 09aeab68033161cb54f194da93e51a11aee6144b`\n- `Linux >= 0626e6641f6b467447c81dd7678a69c66f7746cf < a4261bbc33fbf99b99c80aa3a2c5097611802980`\n- `Linux >= 0626e6641f6b467447c81dd7678a69c66f7746cf < f17d1c63a76b0fe8e9c78023a86507a3a6d62cfa`\n- `Linux >= 0626e6641f6b467447c81dd7678a69c66f7746cf < 3aa660c059240e0c795217182cf7df32909dd917`\n- `Linux 5.15`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":49,"depthScoreParts":{"impact":48.4,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}