{"id":"CVE-2026-98982","revision":null,"records":[{"revision":"a08c2b0b8d5f45619f00d61bfaa0dae5","observedAt":"2026-10-24T16:17:04.479+00:00","statement":{"source":"cve-program","id":"CVE-2026-98982","aliases":[],"title":"namespace: don't let a pseudo dentry become the root of a mount","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnamespace: don't let a pseudo dentry become the root of a mount\n\nd_alloc_pseudo() hands out dentries for pipes, sockets and other files\nthat are never anyone's child or parent. They carry DCACHE_NORCU and\ndentry_free() frees them right away because no lockless path walk can\never reach them. That holds as long as such a dentry isn't the root of\na mount. But bind mounting /proc/self/fd/ of such a file does\nexactly that.\n\nMost callers of alloc_file_pseudo() put their files on kernel-internal\nmounts and may_copy_tree() refuses those. bpf_token_create() doesn't. It\nplaces the token file on the bpffs mount the caller handed it and that\nmount is in the caller's mount namespace so the clone goes through:\n\n mount --bind /proc/self/fd/ \n open_tree(tokfd, \"\", AT_EMPTY_PATH | OPEN_TREE_CLONE) + move_mount()\n\n__follow_mount_rcu() then loads ->mnt_root of that mount, reads d_seq\nand d_flags of the dentry and only then checks mount_lock. The dentry\ncan be gone by then. The final mntput() of an unmounted parent unhooks\na child that stayed attached to it under mount_lock alone. When the\nchild's holder does the final put right after that the root is dput()\nand freed immediately while a walker that found the mount hashed still\nlooks at it.\n\nRefuse to clone a mount with a DCACHE_NORCU dentry as its root. Nothing\nsensible can be done with a bind mount of a bpf token anyway.","state":0,"publishedAt":"2026-10-23T12:19:59.784+00:00","modifiedAt":"2026-10-24T14:09:50.745+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n \"product\": \"Linux\",\n \"vendor\": \"Linux\",\n \"defaultStatus\": \"unaffected\",\n \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n \"programFiles\": [\n \"fs/namespace.c\"\n ],\n \"versions\": [\n {\n \"version\": \"35f96de04127d332a5c5e8a155d31f452f88c76d\",\n \"lessThan\": \"a256e31e0c54c4c37d2523aa52faabdcdd2ebc07\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"35f96de04127d332a5c5e8a155d31f452f88c76d\",\n \"lessThan\": \"7e1c466011ba9e64d43075396badc03191bcee44\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"35f96de04127d332a5c5e8a155d31f452f88c76d\",\n \"lessThan\": \"00287afa7cd989efdbf5822b7efac33cce7d489a\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"35f96de04127d332a5c5e8a155d31f452f88c76d\",\n \"lessThan\": \"b138e16fb1e81376cea89f727dda7bfccd140de4\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n }\n ]\n }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n \"product\": \"Linux\",\n \"vendor\": \"Linux\",\n \"defaultStatus\": \"affected\",\n \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n \"programFiles\": [\n \"fs/namespace.c\"\n ],\n \"versions\": [\n {\n \"version\": \"6.9\",\n \"status\": \"affected\"\n },\n {\n \"version\": \"0\",\n \"lessThan\": \"6.9\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.12.113\",\n \"lessThanOrEqual\": \"6.12.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.18.57\",\n \"lessThanOrEqual\": \"6.18.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"7.2.11\",\n \"lessThanOrEqual\": \"7.2.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"7.3\",\n \"lessThanOrEqual\": \"*\",\n \"status\": \"unaffected\",\n \"versionType\": \"original_commit_for_fix\"\n }\n ]\n }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/a256e31e0c54c4c37d2523aa52faabdcdd2ebc07","https://git.kernel.org/stable/c/7e1c466011ba9e64d43075396badc03191bcee44","https://git.kernel.org/stable/c/00287afa7cd989efdbf5822b7efac33cce7d489a","https://git.kernel.org/stable/c/b138e16fb1e81376cea89f727dda7bfccd140de4"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98982","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-98982","identifiers":["CVE-2026-98982"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. Missing entries do not establish absence of exploitation.","generation":"2026-10-26T00:46:57.9533087+00:00","complete":true,"records":1756,"lastAttemptAt":"2026-10-26T00:46:57.9533087+00:00","lastSuccessAt":"2026-10-26T00:46:58.1070069+00:00","error":null,"lastVerifiedAt":"2026-10-26T00:46:58.1070087+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null},{"source":"cve-program","scope":"Official CVE Program baseline and cumulative hourly delta; all vendors, published and rejected records","generation":"cve-1a687ad2a0b90150aa7d97c9f39e63de695ae2db23e31ebc28df1492c461b23c-8739c76e681f900923b900c9df0ef75cf421d39cabb54650c4b9ad19b6a76d85","complete":true,"records":414048,"lastAttemptAt":"2026-10-26T00:46:56.7781981+00:00","lastSuccessAt":"2026-10-26T00:46:56.7731374+00:00","error":null,"lastVerifiedAt":"2026-10-26T00:46:56.7781981+00:00","snapshotPublishedAt":"2026-10-26T00:42:27+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null},{"source":"euvd","scope":"Rolling EUVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global EUVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-43321610382942b8ad8c85917eab1546","complete":false,"records":4735,"lastAttemptAt":"2026-10-26T00:47:02.6516296+00:00","lastSuccessAt":"2026-10-24T23:18:49.862+00:00","error":"InvalidDataException","lastVerifiedAt":"2026-10-24T23:18:49.862+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":4764,"expectedIdentifiers":13474},{"source":"first-epss:nuget","scope":"FIRST EPSS for explicit CVE aliases in the collected public NuGet archive. Not a global EPSS backfill.","generation":"2026-10-26T00:46:57.9533087+00:00","complete":true,"records":1093,"lastAttemptAt":"2026-10-26T00:46:57.9533087+00:00","lastSuccessAt":"2026-10-26T00:46:58.1082168+00:00","error":null,"lastVerifiedAt":"2026-10-26T00:46:58.1082172+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null},{"source":"nvd","scope":"Rolling NVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global NVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-204a3fb93a00487e8f7f36db01dc851d","complete":true,"records":13413,"lastAttemptAt":"2026-10-26T00:47:00.681998+00:00","lastSuccessAt":"2026-10-25T16:19:28.681+00:00","error":null,"lastVerifiedAt":"2026-10-25T16:19:28.681+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13474,"expectedIdentifiers":13474},{"source":"osv:Go","scope":"Complete OSV Go ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"go-2375a4e597279abf92e8747e140fe8da9d421877cd49cae3ac69a2cb78469b2c","complete":true,"records":9779,"lastAttemptAt":"2026-10-26T00:46:57.4114497+00:00","lastSuccessAt":"2026-10-24T13:19:53.1346702+00:00","error":null,"lastVerifiedAt":"2026-10-26T00:46:57.4114497+00:00","snapshotPublishedAt":"2026-10-24T03:03:12+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null},{"source":"osv:NuGet","scope":"Complete OSV NuGet ecosystem archive, including GitHub Advisory Database records; NuGet version matching only","generation":"nuget-16ad89dfea13ab9e9b0108e63a759d63bd4559cc68b58491107d62ee35bbbaf2","complete":true,"records":1965,"lastAttemptAt":"2026-10-26T00:46:56.9270949+00:00","lastSuccessAt":"2026-10-23T16:01:26.4487605+00:00","error":null,"lastVerifiedAt":"2026-10-26T00:46:56.9270949+00:00","snapshotPublishedAt":"2026-10-21T12:18:07+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null},{"source":"osv:crates.io","scope":"Complete OSV crates.io ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"crates.io-7da67a15aa6e56a0e3081a7646dc74d537e6ef974afc593c2b1794ed01970648","complete":true,"records":2969,"lastAttemptAt":"2026-10-26T00:46:57.8104847+00:00","lastSuccessAt":"2026-10-24T13:19:59.1145547+00:00","error":null,"lastVerifiedAt":"2026-10-26T00:46:57.8104847+00:00","snapshotPublishedAt":"2026-10-24T08:47:51+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null},{"source":"osv:npm","scope":"Complete OSV npm ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"npm-11236ada05a0588e51df37636716526867f73fb127392c49680b6f8561496a99","complete":true,"records":230781,"lastAttemptAt":"2026-10-26T00:46:57.3095832+00:00","lastSuccessAt":"2026-10-25T22:04:07.173333+00:00","error":null,"lastVerifiedAt":"2026-10-26T00:46:57.3095832+00:00","snapshotPublishedAt":"2026-10-25T21:33:06+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null}]}