{"id":"CVE-2026-99169","state":"PUBLISHED","title":"futex: Fix mm reuse handling for FUT_OFF_MMSHARED","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nfutex: Fix mm reuse handling for FUT_OFF_MMSHARED\n\nA FUT_OFF_MMSHARED futex is a shared futex that refers to an MM.\nIt is possible for a process to wait on a shared futex with a different MM\nbecause a FUT_OFF_INODE waiter can be requeued onto a FUT_OFF_MMSHARED\nfutex by another process.\nThis can cause FUT_OFF_MMSHARED waiters on a freed MM to consume\nwakeups intended for a newly allocated MM at the same address.\n\nFix it by keying FUT_OFF_MMSHARED using a unique 64-bit per-MM ID.\nLeave private futexes as before to avoid influencing the performance of the\nhotpath.\n\n(Multi-threaded processes typically implicitly use FUT_OFF_MMSHARED by\nsetting clear_child_tid such that it points into anonymous memory, which\ncauses mm_release() in a multi-threaded mm to perform FUTEX_WAKE.)","publishedAt":"2026-10-28T10:35:20.170Z","updatedAt":"2026-10-30T12:42:34.724Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"222993395ed38f3751287f4bd82ef46b3eb3a66d","status":"affected","lessThan":"096b5d4b80d19b1f7bf8e63fae0d0a32dbb6e1a2","versionType":"git"},{"version":"222993395ed38f3751287f4bd82ef46b3eb3a66d","status":"affected","lessThan":"a7aa4ce1b56a688fe4da75430ec7bf9fe3311807","versionType":"git"},{"version":"222993395ed38f3751287f4bd82ef46b3eb3a66d","status":"affected","lessThan":"f470b76584b5e32d9f9436ef78fb899914116d75","versionType":"git"},{"version":"222993395ed38f3751287f4bd82ef46b3eb3a66d","status":"affected","lessThan":"0c133ed51700036796318f038dde813976bf1227","versionType":"git"},{"version":"222993395ed38f3751287f4bd82ef46b3eb3a66d","status":"affected","lessThan":"16cc0fee39dffd9994b7bea676a886ed52206754","versionType":"git"},{"version":"222993395ed38f3751287f4bd82ef46b3eb3a66d","status":"affected","lessThan":"c17cc2027773e8e4913c5ab0fe3a489b1ed5bf81","versionType":"git"},{"version":"222993395ed38f3751287f4bd82ef46b3eb3a66d","status":"affected","lessThan":"2855ddc6844f527e375e78afb55ec2a5182f23b3","versionType":"git"},{"version":"222993395ed38f3751287f4bd82ef46b3eb3a66d","status":"affected","lessThan":"3267512ad1c2cc0c7768c5b014dc2cceb398a801","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/futex.h","include/linux/futex_types.h","kernel/futex/core.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.7","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.7","versionType":"semver"},{"version":"5.10.273","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.224","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.161","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.115","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.59","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.13","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/futex.h","include/linux/futex_types.h","kernel/futex/core.c"]}],"references":["https://git.kernel.org/stable/c/096b5d4b80d19b1f7bf8e63fae0d0a32dbb6e1a2","https://git.kernel.org/stable/c/a7aa4ce1b56a688fe4da75430ec7bf9fe3311807","https://git.kernel.org/stable/c/f470b76584b5e32d9f9436ef78fb899914116d75","https://git.kernel.org/stable/c/0c133ed51700036796318f038dde813976bf1227","https://git.kernel.org/stable/c/16cc0fee39dffd9994b7bea676a886ed52206754","https://git.kernel.org/stable/c/c17cc2027773e8e4913c5ab0fe3a489b1ed5bf81","https://git.kernel.org/stable/c/2855ddc6844f527e375e78afb55ec2a5182f23b3","https://git.kernel.org/stable/c/3267512ad1c2cc0c7768c5b014dc2cceb398a801"],"weaknesses":[],"ingestedAt":"2026-10-30T13:02:04.640Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/99xxx/CVE-2026-99169.json","commit":"cb14bf1b43b0c9f05f7f40eae2246263fd430780","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-99169","state":"PUBLISHED","datePublished":"2026-10-28T10:35:20.170Z","dateUpdated":"2026-10-30T12:42:34.724Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-25T10:25:14.398Z"},"containers":{"cna":{"title":"futex: Fix mm reuse handling for FUT_OFF_MMSHARED","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nfutex: Fix mm reuse handling for FUT_OFF_MMSHARED\n\nA FUT_OFF_MMSHARED futex is a shared futex that refers to an MM.\nIt is possible for a process to wait on a shared futex with a different MM\nbecause a FUT_OFF_INODE waiter can be requeued onto a FUT_OFF_MMSHARED\nfutex by another process.\nThis can cause FUT_OFF_MMSHARED waiters on a freed MM to consume\nwakeups intended for a newly allocated MM at the same address.\n\nFix it by keying FUT_OFF_MMSHARED using a unique 64-bit per-MM ID.\nLeave private futexes as before to avoid influencing the performance of the\nhotpath.\n\n(Multi-threaded processes typically implicitly use FUT_OFF_MMSHARED by\nsetting clear_child_tid such that it points into anonymous memory, which\ncauses mm_release() in a multi-threaded mm to perform FUTEX_WAKE.)"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"222993395ed38f3751287f4bd82ef46b3eb3a66d","status":"affected","lessThan":"096b5d4b80d19b1f7bf8e63fae0d0a32dbb6e1a2","versionType":"git"},{"version":"222993395ed38f3751287f4bd82ef46b3eb3a66d","status":"affected","lessThan":"a7aa4ce1b56a688fe4da75430ec7bf9fe3311807","versionType":"git"},{"version":"222993395ed38f3751287f4bd82ef46b3eb3a66d","status":"affected","lessThan":"f470b76584b5e32d9f9436ef78fb899914116d75","versionType":"git"},{"version":"222993395ed38f3751287f4bd82ef46b3eb3a66d","status":"affected","lessThan":"0c133ed51700036796318f038dde813976bf1227","versionType":"git"},{"version":"222993395ed38f3751287f4bd82ef46b3eb3a66d","status":"affected","lessThan":"16cc0fee39dffd9994b7bea676a886ed52206754","versionType":"git"},{"version":"222993395ed38f3751287f4bd82ef46b3eb3a66d","status":"affected","lessThan":"c17cc2027773e8e4913c5ab0fe3a489b1ed5bf81","versionType":"git"},{"version":"222993395ed38f3751287f4bd82ef46b3eb3a66d","status":"affected","lessThan":"2855ddc6844f527e375e78afb55ec2a5182f23b3","versionType":"git"},{"version":"222993395ed38f3751287f4bd82ef46b3eb3a66d","status":"affected","lessThan":"3267512ad1c2cc0c7768c5b014dc2cceb398a801","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/futex.h","include/linux/futex_types.h","kernel/futex/core.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.7","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.7","versionType":"semver"},{"version":"5.10.273","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.224","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.161","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.115","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.59","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.13","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/futex.h","include/linux/futex_types.h","kernel/futex/core.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/096b5d4b80d19b1f7bf8e63fae0d0a32dbb6e1a2"},{"url":"https://git.kernel.org/stable/c/a7aa4ce1b56a688fe4da75430ec7bf9fe3311807"},{"url":"https://git.kernel.org/stable/c/f470b76584b5e32d9f9436ef78fb899914116d75"},{"url":"https://git.kernel.org/stable/c/0c133ed51700036796318f038dde813976bf1227"},{"url":"https://git.kernel.org/stable/c/16cc0fee39dffd9994b7bea676a886ed52206754"},{"url":"https://git.kernel.org/stable/c/c17cc2027773e8e4913c5ab0fe3a489b1ed5bf81"},{"url":"https://git.kernel.org/stable/c/2855ddc6844f527e375e78afb55ec2a5182f23b3"},{"url":"https://git.kernel.org/stable/c/3267512ad1c2cc0c7768c5b014dc2cceb398a801"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-30T12:42:34.724Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"5.10.273"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"5.15.224"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"6.1.191"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"6.6.161"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"6.12.115"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"6.18.59"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"7.2.13"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}