{"id":"CVE-2025-40204","title":"sctp: Fix MAC comparison to be constant-time","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: Fix MAC comparison to be constant-time\n\nTo prevent timing attacks, MACs need to be compared in constant time.\nUse the appropriate helper function for this.","severity":"high","cvss":8.1,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < b93fa8dc521d00d2d44bf034fb90e0d79b036617","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 0e8b8c326c2a6de4d837b1bb034ea704f4690d77","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 1cd60e0d0fb8f0e62ec4499138afce6342dc9d4c","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 9c05d44ec24126fc283835b68f82dba3ae985209","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < ed3044b9c810c5c24eb2830053fbfe5fd134c5d4","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 8019b3699289fce3f10b63f98601db97b8d105b0","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 0b32ff285ff6f6f1ac1d9495787ccce8837d6405","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < dd91c79e4f58fbe2898dac84858033700e0e99fb","Linux 2.6.12"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-15T21:58:06.126976Z"},"published":"2025-11-12","updated":"2026-10-15","sourceUpdated":"2026-10-15T22:02:40.705Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2025-40204","references":[{"url":"https://git.kernel.org/stable/c/b93fa8dc521d00d2d44bf034fb90e0d79b036617"},{"url":"https://git.kernel.org/stable/c/0e8b8c326c2a6de4d837b1bb034ea704f4690d77"},{"url":"https://git.kernel.org/stable/c/1cd60e0d0fb8f0e62ec4499138afce6342dc9d4c"},{"url":"https://git.kernel.org/stable/c/9c05d44ec24126fc283835b68f82dba3ae985209"},{"url":"https://git.kernel.org/stable/c/ed3044b9c810c5c24eb2830053fbfe5fd134c5d4"},{"url":"https://git.kernel.org/stable/c/8019b3699289fce3f10b63f98601db97b8d105b0"},{"url":"https://git.kernel.org/stable/c/0b32ff285ff6f6f1ac1d9495787ccce8837d6405"},{"url":"https://git.kernel.org/stable/c/dd91c79e4f58fbe2898dac84858033700e0e99fb"}],"tags":["cve.org"],"epss":0.00463,"epssPercentile":0.38596,"ingestedAt":"2026-10-15T22:48:25.551Z","slug":"CVE-2025-40204","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nsctp: Fix MAC comparison to be constant-time\n\nTo prevent timing attacks, MACs need to be compared in constant time.\nUse the appropriate helper function for this.\n\n## Affected\n\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < b93fa8dc521d00d2d44bf034fb90e0d79b036617`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 0e8b8c326c2a6de4d837b1bb034ea704f4690d77`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 1cd60e0d0fb8f0e62ec4499138afce6342dc9d4c`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 9c05d44ec24126fc283835b68f82dba3ae985209`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < ed3044b9c810c5c24eb2830053fbfe5fd134c5d4`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 8019b3699289fce3f10b63f98601db97b8d105b0`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 0b32ff285ff6f6f1ac1d9495787ccce8837d6405`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < dd91c79e4f58fbe2898dac84858033700e0e99fb`\n- `Linux 2.6.12`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":45,"depthScoreParts":{"impact":44.6,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}