{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-89643", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.741Z", "datePublished": "2026-09-11T19:45:35.523Z", "dateUpdated": "2026-10-19T08:50:15.077Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:50:15.077Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\naudit: avoid dropping live tree ref on fsnotify rule autoremove\n\naudit_del_rule() is used for both netlink deletion templates and internal\nfsnotify autoremove. The former passes a parsed template which owns a\ntemporary tree reference; the latter passes the installed entry itself.\n\nThe unconditional audit_put_tree() at the end of audit_del_rule() assumes\nthe template case. For mixed AUDIT_DIR plus AUDIT_EXE rules, an fsnotify\nautoremove event therefore drops the installed rule's live tree reference.\nRepeating this across rules sharing the same tree can free the tree while\nanother rule still references it, and a later autoremove dereferences the\nfreed pathname while comparing rules.\n\nMove the temporary-tree put to audit_rule_change(), the caller that owns\ndeletion templates. Keep it in the AUDIT_DEL_RULE cleanup so both\nsuccessful deletion and -ENOENT still release the parser-owned tree.\n\n[PM: dropped unnecessary comment for line length reasons]" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL" }, "scenarios": [ { "lang": "en", "value": "AV:N - audit_autoremove_mark_rule() runs from fsnotify FS_MOVE_SELF/FS_DELETE_SELF/FS_UNMOUNT on the AUDIT_EXE parent directory; nfsd and ksmbd vfs_rename/vfs_rmdir of that directory reach the same path over the network, not only local renameat/rmdir.\nAC:L - Each EXE fsnotify autoremove deterministically extra-puts the live shared audit_tree; the attacker issues sequential directory renames/rmdirs they fully control and needs no race or memory layout beyond their influence.\nPR:N - Triggering requires only renaming or rmdir'ing the parent directory of an audited executable on a local or NFS/SMB-exported path; a remote client needs no local account, CAP_AUDIT_CONTROL, or init-namespace root beyond export write access.\nUI:N - The attacker triggers autoremove with their own rename/rmdir (local or via nfsd/ksmbd); no other user must open files, mount a filesystem, or otherwise interact.\nS:U - The use-after-free corrupts host kernel heap (struct audit_tree) and stays within the same kernel security authority; it is not a VM escape, IOMMU bypass, or other documented cross-boundary impact.\nC:H - Use-after-free of the shared audit_tree lets a later audit_compare_rule() strcmp the freed pathname and remaining rules dereference attacker-reclaimed tree objects, enabling arbitrary kernel reads.\nI:H - The dangling tree is then used in audit_remove_tree_rule() list_del/list_move and prune_one() after extra puts free it, enabling heap spraying, list corruption, arbitrary writes, and control-flow hijack.\nA:H - Dereferencing the freed audit_tree pathname or underflowing its refcount during prune oopses/panics the kernel; the UAF can be triggered repeatedly for denial of service." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "kernel/auditfilter.c" ], "versions": [ { "version": "34d99af52ad40bd498ba66970579a5bc1fb1a3bc", "lessThan": "9cac21f8eb82675ed19fb955b8bbb9dd14cc3d58", "status": "affected", "versionType": "git" }, { "version": "34d99af52ad40bd498ba66970579a5bc1fb1a3bc", "lessThan": "b322cc7adcd2e6ec1594d187533a126506ab545c", "status": "affected", "versionType": "git" }, { "version": "34d99af52ad40bd498ba66970579a5bc1fb1a3bc", "lessThan": "695c85dc345a4e0292739f004c261bedef3f27e6", "status": "affected", "versionType": "git" }, { "version": "34d99af52ad40bd498ba66970579a5bc1fb1a3bc", "lessThan": "01b0ec8c397be65ff710777c97017ca1de56ef8e", "status": "affected", "versionType": "git" }, { "version": "34d99af52ad40bd498ba66970579a5bc1fb1a3bc", "lessThan": "cf37b61b5420fd4600fe78cf8c24da6e4d9bfe28", "status": "affected", "versionType": "git" }, { "version": "34d99af52ad40bd498ba66970579a5bc1fb1a3bc", "lessThan": "636a99bab36ba27515363d325866c0273ac83b3e", "status": "affected", "versionType": "git" }, { "version": "34d99af52ad40bd498ba66970579a5bc1fb1a3bc", "lessThan": "583cf579b32d99e3fe4e9c8ecc4d852e3708fbec", "status": "affected", "versionType": "git" }, { "version": "34d99af52ad40bd498ba66970579a5bc1fb1a3bc", "lessThan": "783f0f0974c156aca630f4ffff248671082a098d", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "kernel/auditfilter.c" ], "versions": [ { "version": "4.3", "status": "affected" }, { "version": "0", "lessThan": "4.3", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.270", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.221", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.188", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.157", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.109", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.50", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.4", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.3", "versionEndExcluding": "5.10.270" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.3", "versionEndExcluding": "5.15.221" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.3", "versionEndExcluding": "6.1.188" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.3", "versionEndExcluding": "6.6.157" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.3", "versionEndExcluding": "6.12.109" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.3", "versionEndExcluding": "6.18.50" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.3", "versionEndExcluding": "7.2.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.3", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/9cac21f8eb82675ed19fb955b8bbb9dd14cc3d58" }, { "url": "https://git.kernel.org/stable/c/b322cc7adcd2e6ec1594d187533a126506ab545c" }, { "url": "https://git.kernel.org/stable/c/695c85dc345a4e0292739f004c261bedef3f27e6" }, { "url": "https://git.kernel.org/stable/c/01b0ec8c397be65ff710777c97017ca1de56ef8e" }, { "url": "https://git.kernel.org/stable/c/cf37b61b5420fd4600fe78cf8c24da6e4d9bfe28" }, { "url": "https://git.kernel.org/stable/c/636a99bab36ba27515363d325866c0273ac83b3e" }, { "url": "https://git.kernel.org/stable/c/583cf579b32d99e3fe4e9c8ecc4d852e3708fbec" }, { "url": "https://git.kernel.org/stable/c/783f0f0974c156aca630f4ffff248671082a098d" } ], "title": "audit: avoid dropping live tree ref on fsnotify rule autoremove", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2026-89643", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "yes" }, { "Technical Impact": "total" } ], "version": "2.0.3", "timestamp": "2026-10-16T19:24:59.658694Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T19:26:46.069Z" } } ] } }