{"id":"CVE-2026-74689","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/atm: fix slab-out-of-bounds read in vcc_setsockopt()\n\nvcc_setsockopt() contained an ineffective optlen check:\n  if (__SO_LEVEL_MATCH(optname, level) && optlen != __…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/atm: fix slab-out-of-bounds read in vcc_setsockopt()\n\nvcc_setsockopt() contained an ineffective optlen check:\n  if (__SO_LEVEL_MATCH(optname, level) && optlen != __…","severity":"high","cvss":7.1,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","published":"2026-08-22","updated":"2026-10-14","sourceUpdated":"2026-10-14T13:10:00.187","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-74689","references":[{"url":"https://git.kernel.org/stable/c/2c5988c7349c0b64a7e0441bfc6e1dca54f7116a","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/35f258fee9ed358c6d0f57f91c30bf029c3724af","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6eb6af88710977eb529b558a07294874d8c40c4d","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/9f77c1ab382188f5b51982fab6d913443b6dc59f","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b3bcd5d65ac03c15787b2a5b36c718e26a689336","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d0c80dbb970439bd2eeb0e5effff8c16a5f4e1e3","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd"],"epss":0.00139,"epssPercentile":0.0286,"ingestedAt":"2026-10-14T13:30:58.538Z","slug":"CVE-2026-74689","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnet/atm: fix slab-out-of-bounds read in vcc_setsockopt()\n\nvcc_setsockopt() contained an ineffective optlen check:\n  if (__SO_LEVEL_MATCH(optname, level) && optlen != __SO_SIZE(optname))\n      return -EINVAL;\n\nIf __SO_LEVEL_MATCH(optname, level) evaluated to false (e.g. if the caller\npassed a mismatched level), the length check optlen != __SO_SIZE(optname)\nwas short-circuited and bypassed. Execution then fell through to switch(optname),\ncalling copy_from_sockptr() assuming optval contained sufficient space.\n\nFurthermore, even if level matched, a cgroup BPF setsockopt filter could shrink\noptlen after entry. Because copy_from_sockptr() on kernel pointers uses memcpy(),\nthis leads to a KASAN slab-out-of-bounds read when optlen is smaller than the\nexpected structure size.\n\nFix this by using copy_safe_from_sockptr(), which unconditionally validates\nthat optlen is at least the expected size before copying. Also change the local\n'value' variable type from 'unsigned long' to 'int' so that SO_SETCLP matches\nits sizeof(int) ABI encoding on 64-bit systems.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":39.1,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}