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vuln-cve/data/2026/97xxx/CVE-2026-97594.json
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{
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"cveMetadata": {
"cveId": "CVE-2026-97594",
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"state": "PUBLISHED",
"assignerShortName": "Linux",
"dateReserved": "2026-09-24T16:01:01.157Z",
"datePublished": "2026-09-25T10:22:10.548Z",
"dateUpdated": "2026-10-30T12:37:31.781Z"
},
"containers": {
"cna": {
"providerMetadata": {
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux",
"dateUpdated": "2026-10-30T12:37:31.781Z"
},
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nlandlock: Fix use-after-free of the source's parent directory\n\ncurrent_check_refer_path() reads old_dentry->d_parent without holding a\nreference nor a lock on it, and then dereferences it in\ncollect_domain_accesses() and in the audit record.\n\nA reference on a child does not pin its parent: __d_move() reassigns\ndentry->d_parent and drops the reference the child held on its former\nparent. hook_path_rename() is not affected because the rename path\ncalls lock_rename() before the hook, so the source cannot be reparented\nunder it. hook_path_link() has no such protection: filename_linkat()\nholds a reference on the source dentry but neither locks nor references\nits parent, so a concurrent rename(2) can reparent the source while\nsecurity_path_link() runs, and the former parent can then be removed and\nfreed while the hook walks it.\n\nA process can trigger this after entering a Landlock domain that handles\nat least one filesystem access right. The process can then race a\nlinkat(2) loop against rename(2) and rmdir(2):\n\n BUG: KASAN: slab-use-after-free in collect_domain_accesses+0x278/0x290\n Read of size 4 at addr ffff888160bd53f4 by task llrepro2/549\n collect_domain_accesses+0x278/0x290\n current_check_refer_path+0x952/0x1120\n security_path_link+0x1be/0x320\n filename_linkat+0x342/0x6d0\n __x64_sys_linkat+0xfa/0x150\n Freed by task 562:\n kmem_cache_free+0x139/0x4c0\n i_callback+0x4b/0x80\n rcu_core+0x7dc/0x10a0\n\nTake a reference on the dentry selected as the source parent, using\ndget() for the common-mount-root case and dget_parent() otherwise.\nRelease it after the hierarchy walk and synchronous audit logging.\n\n[mic: Clarify the caller, reachability, and reference handling]"
}
],
"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 trigger is a local linkat(2) syscall: filename_linkat() -> security_path_link() -> hook_path_link() -> current_check_refer_path(), raced against local rename(2)/rmdir(2). No remote protocol supplies any of the input.\nAC:L - The attacker runs every side of the race: a linkat() loop on their own file, plus rename() to reparent the source and rmdir() to free the old parent, all in directories they create (e.g. /tmp). No condition outside the attacker's control is needed; the window can be retried at will.\nPR:L - An ordinary unprivileged user can enter a Landlock domain that handles any FS right (landlock_create_ruleset + landlock_restrict_self after PR_SET_NO_NEW_PRIVS, no capability needed); that makes landlock_get_applicable_subject() non-NULL and reaches the unpinned d_parent read.\nUI:N - The attacker's own syscalls on files and directories they own trigger the bug; no other user or administrator has to do anything.\nS:U - The corruption happens in kernel memory under the same kernel authority; exploiting it is standard local privilege escalation, not a crossing into a separate authority such as a hypervisor.\nC:H - collect_domain_accesses() dereferences the freed old_parent dentry and follows its d_parent/d_inode pointers into the Landlock inode blob via find_rule(). If the attacker reallocates the freed slab, they control pointers that the kernel then follows and reads.\nI:H - collect_domain_accesses() calls dget() and later dput() on the freed dentry. That writes the lockref inside the freed or reallocated object and can run dentry teardown on it, a write primitive that can lead to a double free or control-flow hijack.\nA:H - The KASAN report in the commit shows a slab use-after-free in collect_domain_accesses(). On production kernels the refcount changes on freed memory or the stale pointer walk can oops or panic the kernel."
}
]
}
],
"affected": [
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"security/landlock/fs.c"
],
"versions": [
{
"version": "b91c3e4ea756b12b7d992529226edce1cfd854d7",
"lessThan": "0475440ff8c04be26a88733af0c85f597bb28c0a",
"status": "affected",
"versionType": "git"
},
{
"version": "b91c3e4ea756b12b7d992529226edce1cfd854d7",
"lessThan": "48fc1c74052c956c59d5b16b5e18e0dd36b76aa2",
"status": "affected",
"versionType": "git"
},
{
"version": "b91c3e4ea756b12b7d992529226edce1cfd854d7",
"lessThan": "4c37992b9668c4f37aae41dd95c369f7b6009915",
"status": "affected",
"versionType": "git"
},
{
"version": "b91c3e4ea756b12b7d992529226edce1cfd854d7",
"lessThan": "379efd2ce8b26fd35feb13ccc2f671ff105a5052",
"status": "affected",
"versionType": "git"
},
{
"version": "b91c3e4ea756b12b7d992529226edce1cfd854d7",
"lessThan": "ba29c46ccfe3ebadfb8aa18149186c49f84b14f8",
"status": "affected",
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{
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"lessThan": "2c6dc792538260a8087ac5b22c31b3b8e47c85d6",
"status": "affected",
"versionType": "git"
}
]
},
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "affected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"security/landlock/fs.c"
],
"versions": [
{
"version": "5.19",
"status": "affected"
},
{
"version": "0",
"lessThan": "5.19",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.1.191",
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.6.160",
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.12.112",
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.18.53",
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "7.2.7",
"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": "5.19",
"versionEndExcluding": "6.1.191"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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"versionEndExcluding": "6.12.112"
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{
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"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.19",
"versionEndExcluding": "6.18.53"
},
{
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"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.19",
"versionEndExcluding": "7.2.7"
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{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.19",
"versionEndExcluding": "7.3"
}
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],
"references": [
{
"url": "https://git.kernel.org/stable/c/0475440ff8c04be26a88733af0c85f597bb28c0a"
},
{
"url": "https://git.kernel.org/stable/c/48fc1c74052c956c59d5b16b5e18e0dd36b76aa2"
},
{
"url": "https://git.kernel.org/stable/c/4c37992b9668c4f37aae41dd95c369f7b6009915"
},
{
"url": "https://git.kernel.org/stable/c/379efd2ce8b26fd35feb13ccc2f671ff105a5052"
},
{
"url": "https://git.kernel.org/stable/c/ba29c46ccfe3ebadfb8aa18149186c49f84b14f8"
},
{
"url": "https://git.kernel.org/stable/c/2c6dc792538260a8087ac5b22c31b3b8e47c85d6"
}
],
"title": "landlock: Fix use-after-free of the source's parent directory",
"x_generator": {
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}