{"id":"CVE-2025-21638","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: sysctl: auth_enable: avoid using current->nsproxy\n\nAs mentioned in a previous commit of this series, using the 'net'\nstructure via 'current' is not recommended fo…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: sysctl: auth_enable: avoid using current->nsproxy\n\nAs mentioned in a previous commit of this series, using the 'net'\nstructure via 'current' is not recommended fo…","severity":"high","cvss":7.1,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H","cwe":["CWE-476"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 3.10.41, < 3.11","linux_kernel >= 3.12.20, < 3.13","linux_kernel >= 3.14.5, < 5.4.290","linux_kernel >= 5.5, < 5.10.234","linux_kernel >= 5.11, < 5.15.177","linux_kernel >= 5.16, < 6.1.125","linux_kernel >= 6.2, < 6.6.72","linux_kernel >= 6.7, < 6.12.10","linux_kernel = 6.13"],"patched":["linux_kernel 6.12.10"],"published":"2025-01-19","updated":"2026-07-30","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2025-21638","references":[{"url":"https://git.kernel.org/stable/c/15649fd5415eda664ef35780c2013adeb5d9c695","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/1b67030d39f2b00f94ac1f0af11ba6657589e4d3","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7ec30c54f339c640aa7e49d7e9f7bbed6bd42bf6","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/bd2a2939423566c654545fa3e96a656662a0af9e","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/c184bc621e3cef03ac9ba81a50dda2dae6a21d36","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/cf387cdebfaebae228dfba162f94c567a67610c3","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/dc583e7e5f8515ca489c0df28e4362a70eade382","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-265688.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd"],"epss":0.00237,"epssPercentile":0.14948,"ingestedAt":"2026-07-30T06:53:08.852Z","slug":"CVE-2025-21638","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nsctp: sysctl: auth_enable: avoid using current->nsproxy\n\nAs mentioned in a previous commit of this series, using the 'net'\nstructure via '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 'net' structure can be obtained from the table->data using\ncontainer_of().\n\nNote that table->data could also be used directly, but that would\nincrease the size of this fix, while 'sctp.ctl_sock' still needs to be\nretrieved from 'net' structure.\n\n## Affected\n\n- `linux_kernel >= 3.10.41, < 3.11`\n- `linux_kernel >= 3.12.20, < 3.13`\n- `linux_kernel >= 3.14.5, < 5.4.290`\n- `linux_kernel >= 5.5, < 5.10.234`\n- `linux_kernel >= 5.11, < 5.15.177`\n- `linux_kernel >= 5.16, < 6.1.125`\n- `linux_kernel >= 6.2, < 6.6.72`\n- `linux_kernel >= 6.7, < 6.12.10`\n- `linux_kernel = 6.13`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 6.12.10`","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":39.1,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}