{"id":"CVE-2026-46150","state":"PUBLISHED","title":"fanotify: fix false positive on permission events","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nfanotify: fix false positive on permission events\n\nfsnotify_get_mark_safe() may return false for a mark on an unrelated group,\nwhich results in bypassing the permission check.\n\nFix by skipping over detached marks that are not in the current group.","publishedAt":"2026-05-28T09:36:06.494Z","updatedAt":"2026-10-19T19:36:52.765Z","severity":{"score":7.1,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"abc77577a669f424c5d0c185b9994f2621c52aa4","status":"affected","lessThan":"a24765332e129c1916d5a6615418b75599b8fcdc","versionType":"git"},{"version":"abc77577a669f424c5d0c185b9994f2621c52aa4","status":"affected","lessThan":"4a7611ad653785fcdea5ff5f4441e2b7d05b7f11","versionType":"git"},{"version":"abc77577a669f424c5d0c185b9994f2621c52aa4","status":"affected","lessThan":"04bb66be92f48ed13c3faf1139d892df228789bc","versionType":"git"},{"version":"abc77577a669f424c5d0c185b9994f2621c52aa4","status":"affected","lessThan":"895ebbedf88318607c24acc0f591c74b165e1d0a","versionType":"git"},{"version":"abc77577a669f424c5d0c185b9994f2621c52aa4","status":"affected","lessThan":"f130790f1acc8399f32652846c875a251efd040f","versionType":"git"},{"version":"abc77577a669f424c5d0c185b9994f2621c52aa4","status":"affected","lessThan":"7baa02b0ae9d17ec5f08836d8ea88ce1927d0678","versionType":"git"},{"version":"abc77577a669f424c5d0c185b9994f2621c52aa4","status":"affected","lessThan":"b7b24b28c8cd55844cab908f4f39dded638d5538","versionType":"git"},{"version":"abc77577a669f424c5d0c185b9994f2621c52aa4","status":"affected","lessThan":"7746e3bd4cc19b5092e00d32d676e329bfcb6900","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/notify/fsnotify.c","fs/notify/mark.c","include/linux/fsnotify_backend.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.12","versionType":"semver"},{"version":"5.10.258","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.209","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.175","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.140","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.88","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.30","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.7","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/notify/fsnotify.c","fs/notify/mark.c","include/linux/fsnotify_backend.h"]}],"references":["https://git.kernel.org/stable/c/a24765332e129c1916d5a6615418b75599b8fcdc","https://git.kernel.org/stable/c/4a7611ad653785fcdea5ff5f4441e2b7d05b7f11","https://git.kernel.org/stable/c/04bb66be92f48ed13c3faf1139d892df228789bc","https://git.kernel.org/stable/c/895ebbedf88318607c24acc0f591c74b165e1d0a","https://git.kernel.org/stable/c/f130790f1acc8399f32652846c875a251efd040f","https://git.kernel.org/stable/c/7baa02b0ae9d17ec5f08836d8ea88ce1927d0678","https://git.kernel.org/stable/c/b7b24b28c8cd55844cab908f4f39dded638d5538","https://git.kernel.org/stable/c/7746e3bd4cc19b5092e00d32d676e329bfcb6900","https://cert-portal.siemens.com/productcert/html/ssa-784472.html"],"weaknesses":["CWE-863"],"ingestedAt":"2026-10-29T20:12:07.131Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/46xxx/CVE-2026-46150.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-46150","state":"PUBLISHED","datePublished":"2026-05-28T09:36:06.494Z","dateUpdated":"2026-10-19T19:36:52.765Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-05-13T15:03:33.101Z"},"containers":{"cna":{"title":"fanotify: fix false positive on permission events","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nfanotify: fix false positive on permission events\n\nfsnotify_get_mark_safe() may return false for a mark on an unrelated group,\nwhich results in bypassing the permission check.\n\nFix by skipping over detached marks that are not in the current group."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"abc77577a669f424c5d0c185b9994f2621c52aa4","status":"affected","lessThan":"a24765332e129c1916d5a6615418b75599b8fcdc","versionType":"git"},{"version":"abc77577a669f424c5d0c185b9994f2621c52aa4","status":"affected","lessThan":"4a7611ad653785fcdea5ff5f4441e2b7d05b7f11","versionType":"git"},{"version":"abc77577a669f424c5d0c185b9994f2621c52aa4","status":"affected","lessThan":"04bb66be92f48ed13c3faf1139d892df228789bc","versionType":"git"},{"version":"abc77577a669f424c5d0c185b9994f2621c52aa4","status":"affected","lessThan":"895ebbedf88318607c24acc0f591c74b165e1d0a","versionType":"git"},{"version":"abc77577a669f424c5d0c185b9994f2621c52aa4","status":"affected","lessThan":"f130790f1acc8399f32652846c875a251efd040f","versionType":"git"},{"version":"abc77577a669f424c5d0c185b9994f2621c52aa4","status":"affected","lessThan":"7baa02b0ae9d17ec5f08836d8ea88ce1927d0678","versionType":"git"},{"version":"abc77577a669f424c5d0c185b9994f2621c52aa4","status":"affected","lessThan":"b7b24b28c8cd55844cab908f4f39dded638d5538","versionType":"git"},{"version":"abc77577a669f424c5d0c185b9994f2621c52aa4","status":"affected","lessThan":"7746e3bd4cc19b5092e00d32d676e329bfcb6900","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/notify/fsnotify.c","fs/notify/mark.c","include/linux/fsnotify_backend.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.12","versionType":"semver"},{"version":"5.10.258","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.209","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.175","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.140","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.88","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.30","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.7","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/notify/fsnotify.c","fs/notify/mark.c","include/linux/fsnotify_backend.h"]}],"references":[{"url":"https://git.kernel.org/stable/c/a24765332e129c1916d5a6615418b75599b8fcdc"},{"url":"https://git.kernel.org/stable/c/4a7611ad653785fcdea5ff5f4441e2b7d05b7f11"},{"url":"https://git.kernel.org/stable/c/04bb66be92f48ed13c3faf1139d892df228789bc"},{"url":"https://git.kernel.org/stable/c/895ebbedf88318607c24acc0f591c74b165e1d0a"},{"url":"https://git.kernel.org/stable/c/f130790f1acc8399f32652846c875a251efd040f"},{"url":"https://git.kernel.org/stable/c/7baa02b0ae9d17ec5f08836d8ea88ce1927d0678"},{"url":"https://git.kernel.org/stable/c/b7b24b28c8cd55844cab908f4f39dded638d5538"},{"url":"https://git.kernel.org/stable/c/7746e3bd4cc19b5092e00d32d676e329bfcb6900"}],"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:N","baseScore":7.1,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The vulnerable code runs in the context of a local file operation (open/read/exec) that triggers the fanotify permission event; the attacker bypasses the control by performing local file ops plus churning a local inotify watch. The fully-controllable, reliable attack is local (a remote file-server scenario would lose attacker control of the race).\nAC:L - The attacker controls both sides of the race — the lifecycle of the unrelated (unprivileged inotify) mark and the retried file operation — and each open() is a fresh permission event, so with unlimited retries the bypass is reliably reachable.\nPR:L - Exploitation only needs an unprivileged local account: creating an inotify watch on the parent directory and opening/executing the target file require no capabilities (the privileged CAP_SYS_ADMIN fanotify group is the victim control, not the attacker).\nUI:N - The attacker performs all actions (inotify churn plus repeated file access) with no interaction from any other user.\nS:U - The flaw and its impact are both mediated entirely within the kernel's own access-control path; no boundary to a separately-managed security authority (VM, IOMMU) is crossed.\nC:H - Bypassing FAN_ACCESS_PERM/FAN_OPEN_PERM lets read access to files the policy (AV/sandbox/EDR) would deny proceed; via targeted retries the attacker can force disclosure of chosen protected files, approaching total loss of confidentiality of protected resources.\nI:H - Bypassing FAN_OPEN_PERM/FAN_OPEN_EXEC_PERM lets writes to protected files and execution of binaries the policy would block proceed, allowing modification of protected resources and execution of disallowed code.\nA:N - The bug is fail-open (it only allows operations that should be blocked); it causes no crash, hang, or resource exhaustion, so availability is unaffected."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:30:03.577Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"5.10.258"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"5.15.209"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"6.1.175"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"6.6.140"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"6.12.88"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"6.18.30"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"7.0.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"7.1"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"affected":[{"vendor":"Siemens","product":"SIMATIC S7-1500 TM MFP - GNU/Linux subsystem","defaultStatus":"unknown","versions":[{"version":"0","status":"affected","lessThan":"*","versionType":"custom"}]}],"references":[{"url":"https://cert-portal.siemens.com/productcert/html/ssa-784472.html"}],"providerMetadata":{"shortName":"siemens-SADP","orgId":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","dateUpdated":"2026-10-15T01:20:50.275Z"},"x_adpType":"supplier"},{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-46150","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T15:20:28.641291Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-863","lang":"en","type":"CWE","description":"CWE-863 Incorrect Authorization"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T19:36:52.765Z"}}]}}}