{"id":"CVE-2025-21641","state":"PUBLISHED","title":"mptcp: sysctl: blackhole timeout: avoid using current->nsproxy","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: sysctl: blackhole timeout: avoid using current->nsproxy\n\nAs mentioned in the previous commit, using the 'net' structure via\n'current' is not recommended for different reasons:\n\n- Inconsistency: getting info from the reader's/writer's netns vs only\n  from the opener's netns.\n\n- current->nsproxy can be NULL in some cases, resulting in an 'Oops'\n  (null-ptr-deref), e.g. when the current task is exiting, as spotted by\n  syzbot [1] using acct(2).\n\nThe 'pernet' structure can be obtained from the table->data using\ncontainer_of().","publishedAt":"2025-01-19T10:17:58.351Z","updatedAt":"2026-05-11T21:03:36.580Z","severity":{"score":5.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","source":"CISA-ADP"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"27069e7cb3d1cea9377069266acf19b9cc5ad0ae","status":"affected","lessThan":"4c74fbdc5ab95b13945be01e6065940b68222db7","versionType":"git"},{"version":"27069e7cb3d1cea9377069266acf19b9cc5ad0ae","status":"affected","lessThan":"92cf7a51bdae24a32c592adcdd59a773ae149289","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/mptcp/ctrl.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.12","versionType":"semver"},{"version":"6.12.10","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.13","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/mptcp/ctrl.c"]}],"references":["https://git.kernel.org/stable/c/4c74fbdc5ab95b13945be01e6065940b68222db7","https://git.kernel.org/stable/c/92cf7a51bdae24a32c592adcdd59a773ae149289"],"weaknesses":["CWE-476"],"ingestedAt":"2026-10-29T20:08:39.238Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/21xxx/CVE-2025-21641.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-21641","state":"PUBLISHED","datePublished":"2025-01-19T10:17:58.351Z","dateUpdated":"2026-05-11T21:03:36.580Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2024-12-29T08:45:45.727Z"},"containers":{"cna":{"title":"mptcp: sysctl: blackhole timeout: avoid using current->nsproxy","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: sysctl: blackhole timeout: avoid using current->nsproxy\n\nAs mentioned in the previous commit, using the 'net' structure via\n'current' is not recommended for different reasons:\n\n- Inconsistency: getting info from the reader's/writer's netns vs only\n  from the opener's netns.\n\n- current->nsproxy can be NULL in some cases, resulting in an 'Oops'\n  (null-ptr-deref), e.g. when the current task is exiting, as spotted by\n  syzbot [1] using acct(2).\n\nThe 'pernet' structure can be obtained from the table->data using\ncontainer_of()."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"27069e7cb3d1cea9377069266acf19b9cc5ad0ae","status":"affected","lessThan":"4c74fbdc5ab95b13945be01e6065940b68222db7","versionType":"git"},{"version":"27069e7cb3d1cea9377069266acf19b9cc5ad0ae","status":"affected","lessThan":"92cf7a51bdae24a32c592adcdd59a773ae149289","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/mptcp/ctrl.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.12","versionType":"semver"},{"version":"6.12.10","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.13","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/mptcp/ctrl.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/4c74fbdc5ab95b13945be01e6065940b68222db7"},{"url":"https://git.kernel.org/stable/c/92cf7a51bdae24a32c592adcdd59a773ae149289"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T21:03:36.580Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"6.12.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"6.13"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":5.5,"attackVector":"LOCAL","baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"LOW","confidentialityImpact":"NONE"}},{"other":{"type":"ssvc","content":{"id":"CVE-2025-21641","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2025-10-01T19:54:04.133628Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-476","lang":"en","type":"CWE","description":"CWE-476 NULL Pointer Dereference"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2025-10-01T19:57:17.498Z"}}]}}}