{"id":"CVE-2026-74330","state":"PUBLISHED","title":"configfs: fix lockless traversals of ->s_children","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nconfigfs: fix lockless traversals of ->s_children\n\nHaving the parent directory locked protects entries from removal\nby another thread, but it does *not* protect cursors from being\nmoved around by lseek() - or freed, for that matter.","publishedAt":"2026-08-15T05:58:23.722Z","updatedAt":"2026-10-16T18:55:33.381Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"6f61076406251626be39651d114fac412b1e0c39","status":"affected","lessThan":"77fd6f50f633a52c2db061e7d71d8cb486b0265e","versionType":"git"},{"version":"6f61076406251626be39651d114fac412b1e0c39","status":"affected","lessThan":"91f289728ec706b7ff1ca0ee845dd73ff2253488","versionType":"git"},{"version":"6f61076406251626be39651d114fac412b1e0c39","status":"affected","lessThan":"b166ab78dc3f48e83d2c80bdfde4159b31fdc5fb","versionType":"git"},{"version":"6f61076406251626be39651d114fac412b1e0c39","status":"affected","lessThan":"9e57e2863872e82e7c7237bc32299f67ebebc543","versionType":"git"},{"version":"6f61076406251626be39651d114fac412b1e0c39","status":"affected","lessThan":"459860529c109c5ce08b81c0776ca1200eaaeb4a","versionType":"git"},{"version":"6f61076406251626be39651d114fac412b1e0c39","status":"affected","lessThan":"637ef4961470e04455102b34ac484a34d8eca0a4","versionType":"git"},{"version":"6f61076406251626be39651d114fac412b1e0c39","status":"affected","lessThan":"e6d93108e0a27d7e6f95c7e45017d14ba2900d32","versionType":"git"},{"version":"6f61076406251626be39651d114fac412b1e0c39","status":"affected","lessThan":"9b9e8bb81c41fd27e7b57a1c936fde140548535f","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/configfs/dir.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.27","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.27","versionType":"semver"},{"version":"5.10.261","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.212","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.178","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.97","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/configfs/dir.c"]}],"references":["https://git.kernel.org/stable/c/77fd6f50f633a52c2db061e7d71d8cb486b0265e","https://git.kernel.org/stable/c/91f289728ec706b7ff1ca0ee845dd73ff2253488","https://git.kernel.org/stable/c/b166ab78dc3f48e83d2c80bdfde4159b31fdc5fb","https://git.kernel.org/stable/c/9e57e2863872e82e7c7237bc32299f67ebebc543","https://git.kernel.org/stable/c/459860529c109c5ce08b81c0776ca1200eaaeb4a","https://git.kernel.org/stable/c/637ef4961470e04455102b34ac484a34d8eca0a4","https://git.kernel.org/stable/c/e6d93108e0a27d7e6f95c7e45017d14ba2900d32","https://git.kernel.org/stable/c/9b9e8bb81c41fd27e7b57a1c936fde140548535f"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/74xxx/CVE-2026-74330.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-74330","state":"PUBLISHED","datePublished":"2026-08-15T05:58:23.722Z","dateUpdated":"2026-10-16T18:55:33.381Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-15T05:44:03.885Z"},"containers":{"cna":{"title":"configfs: fix lockless traversals of ->s_children","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nconfigfs: fix lockless traversals of ->s_children\n\nHaving the parent directory locked protects entries from removal\nby another thread, but it does *not* protect cursors from being\nmoved around by lseek() - or freed, for that matter."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"6f61076406251626be39651d114fac412b1e0c39","status":"affected","lessThan":"77fd6f50f633a52c2db061e7d71d8cb486b0265e","versionType":"git"},{"version":"6f61076406251626be39651d114fac412b1e0c39","status":"affected","lessThan":"91f289728ec706b7ff1ca0ee845dd73ff2253488","versionType":"git"},{"version":"6f61076406251626be39651d114fac412b1e0c39","status":"affected","lessThan":"b166ab78dc3f48e83d2c80bdfde4159b31fdc5fb","versionType":"git"},{"version":"6f61076406251626be39651d114fac412b1e0c39","status":"affected","lessThan":"9e57e2863872e82e7c7237bc32299f67ebebc543","versionType":"git"},{"version":"6f61076406251626be39651d114fac412b1e0c39","status":"affected","lessThan":"459860529c109c5ce08b81c0776ca1200eaaeb4a","versionType":"git"},{"version":"6f61076406251626be39651d114fac412b1e0c39","status":"affected","lessThan":"637ef4961470e04455102b34ac484a34d8eca0a4","versionType":"git"},{"version":"6f61076406251626be39651d114fac412b1e0c39","status":"affected","lessThan":"e6d93108e0a27d7e6f95c7e45017d14ba2900d32","versionType":"git"},{"version":"6f61076406251626be39651d114fac412b1e0c39","status":"affected","lessThan":"9b9e8bb81c41fd27e7b57a1c936fde140548535f","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/configfs/dir.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.27","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.27","versionType":"semver"},{"version":"5.10.261","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.212","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.178","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.97","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/configfs/dir.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/77fd6f50f633a52c2db061e7d71d8cb486b0265e"},{"url":"https://git.kernel.org/stable/c/91f289728ec706b7ff1ca0ee845dd73ff2253488"},{"url":"https://git.kernel.org/stable/c/b166ab78dc3f48e83d2c80bdfde4159b31fdc5fb"},{"url":"https://git.kernel.org/stable/c/9e57e2863872e82e7c7237bc32299f67ebebc543"},{"url":"https://git.kernel.org/stable/c/459860529c109c5ce08b81c0776ca1200eaaeb4a"},{"url":"https://git.kernel.org/stable/c/637ef4961470e04455102b34ac484a34d8eca0a4"},{"url":"https://git.kernel.org/stable/c/e6d93108e0a27d7e6f95c7e45017d14ba2900d32"},{"url":"https://git.kernel.org/stable/c/9b9e8bb81c41fd27e7b57a1c936fde140548535f"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The bug is reached only through local VFS syscalls (openat, getdents, lseek, close, mkdir, rmdir) against configfs, typically mounted at /sys/kernel/config; it is not reachable via network-facing kernel services such as ksmbd, nfsd, or packet-receive paths.\nAC:L - The attacker controls both sides of the race: opening a configfs directory inserts a readdir cursor into s_children, and concurrent lseek() or close() moves or frees that cursor while detach_attrs, detach_groups, or configfs_find_subsys_dentry traverse the list without configfs_dirent_lock; the window is attacker-driven and retryable.\nPR:L - Default configfs trees are root-owned, but 0755 directories let any local user open and lseek while teardown races proceed; USB gadget, target/LIO, gpio-aggregator, and embedded deployments commonly grant configfs mkdir/rmdir/write to service accounts or expose world-writable (S_IWUGO) gadget attributes.\nUI:N - Exploitation requires only the attacker issuing syscalls and spawning concurrent threads against configfs paths mounted at boot; no victim must mount filesystems, click prompts, or open files on the attacker's behalf.\nS:U - Slab use-after-free and list corruption impact kernel memory within the same security domain; this enables local privilege escalation, not VM escape, IOMMU bypass, or sandbox boundary crossing.\nC:H - Lockless s_children traversal can follow a freed readdir cursor (the fix commit notes cursors can be \"freed\"), dereferencing kmem_cache_freed configfs_dirent objects and yielding standard slab UAF read primitives over adjacent kernel heap contents.\nI:H - The dangling cursor and list corruption enable heap grooming to reclaim freed configfs_dirent slabs and convert the race into arbitrary kernel writes or control-flow hijack, not merely incorrect metadata updates.\nA:H - Concurrent cursor free or move during unlocked list iteration causes kernel oops or panic via invalid list pointers or UAF dereferences; the race is repeatable for sustained denial of service."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-17T05:45:56.848Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.27","versionEndExcluding":"5.10.261"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.27","versionEndExcluding":"5.15.212"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.27","versionEndExcluding":"6.1.178"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.27","versionEndExcluding":"6.6.145"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.27","versionEndExcluding":"6.12.97"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.27","versionEndExcluding":"6.18.40"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.27","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.27","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-74330","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T18:53:38.426729Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-16T18:55:33.381Z"}}]}}}