{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-98989", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.384Z", "datePublished": "2026-10-23T12:20:08.366Z", "dateUpdated": "2026-10-23T12:20:08.366Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-23T12:20:08.366Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnamespace: check a recursive bind mount for mount namespace loops\n\ndo_loopback() refuses to bind mount the file of a mount namespace that\nis as old as the caller's or older because a mount namespace that holds\na mount of its own file, or of an ancestor's, would cause a cycle. But\nit only checks the dentry the bind mount starts from. With MS_REC\neverything below it is copied and do_loopback() passes\nCL_COPY_MNT_NS_FILE so mount namespace files below the source are\ncopied.\n\nThat's fine for a source in the caller's own mount namespace. Every\nmount namespace file in there passed the same check when it was\nbind-mounted. It isn't fine for a source in another mount namespace.\nmay_copy_tree() accepts a bind mount of any nsfs or pidfs file no matter\nwhat mount namespace it lives in so that /proc/<pid>/ns/<ns> and pidfds\ncan be bind mounted. If we create a bind-mount stack of mount namespaces\nfile descriptors the kernel will copy them irrespective of their\nancestoral relationship to the mount namespace in question:\n\n 151 146 0:7 net:[4026531833] /tmp/nrc/y rw - nsfs nsfs rw\n 152 151 0:7 mnt:[4026532293] /tmp/nrc/y rw - nsfs nsfs rw\n\nMount 152 is a mount of the mount namespace file of mount namespace\n4026532293 inside mount namespace 4026532293. That namespace and every\nmount in it are leaked... All it takes is a process in an older mount\nnamespace that stacks the file and repeating it leaks without limit:\n\n after control: Shmem: 380 kB\n child: mount(/proc/self/fd/6, MS_BIND|MS_REC): ok\n after cycle: Shmem: 65916 kB\n\ndo_move_mount() runs check_for_nsfs_mounts() over a detached tree for\nexactly that reason. Do the same for the copy before it is grafted."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/namespace.c"], "versions": [{"version": "e149ed2b805fefdccf7ccdfc19eca22fdd4514ac", "lessThan": "a0ba48256f5dff6f75a45f8ce39fe57f21df1022", "status": "affected", "versionType": "git"}, {"version": "e149ed2b805fefdccf7ccdfc19eca22fdd4514ac", "lessThan": "37a82f400efa4d263542a5fa41755b21057f1e5d", "status": "affected", "versionType": "git"}, {"version": "e149ed2b805fefdccf7ccdfc19eca22fdd4514ac", "lessThan": "c640a01a78e42302879006ed7b7d5a9a943ba815", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/namespace.c"], "versions": [{"version": "3.19", "status": "affected"}, {"version": "0", "lessThan": "3.19", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.57", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.11", "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": "3.19", "versionEndExcluding": "6.18.57"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.19", "versionEndExcluding": "7.2.11"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.19", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/a0ba48256f5dff6f75a45f8ce39fe57f21df1022"}, {"url": "https://git.kernel.org/stable/c/37a82f400efa4d263542a5fa41755b21057f1e5d"}, {"url": "https://git.kernel.org/stable/c/c640a01a78e42302879006ed7b7d5a9a943ba815"}], "title": "namespace: check a recursive bind mount for mount namespace loops", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/namespace.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "a0ba48256f5dff6f75a45f8ce39fe57f21df1022", "status": "affected", "version": "e149ed2b805fefdccf7ccdfc19eca22fdd4514ac", "versionType": "git"}, {"lessThan": "37a82f400efa4d263542a5fa41755b21057f1e5d", "status": "affected", "version": "e149ed2b805fefdccf7ccdfc19eca22fdd4514ac", "versionType": "git"}, {"lessThan": "c640a01a78e42302879006ed7b7d5a9a943ba815", "status": "affected", "version": "e149ed2b805fefdccf7ccdfc19eca22fdd4514ac", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/namespace.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "3.19"}, {"lessThan": "3.19", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.57", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.11", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnamespace: check a recursive bind mount for mount namespace loops\n\ndo_loopback() refuses to bind mount the file of a mount namespace that\nis as old as the caller's or older because a mount namespace that holds\na mount of its own file, or of an ancestor's, would cause a cycle. But\nit only checks the dentry the bind mount starts from. With MS_REC\neverything below it is copied and do_loopback() passes\nCL_COPY_MNT_NS_FILE so mount namespace files below the source are\ncopied.\n\nThat's fine for a source in the caller's own mount namespace. Every\nmount namespace file in there passed the same check when it was\nbind-mounted. It isn't fine for a source in another mount namespace.\nmay_copy_tree() accepts a bind mount of any nsfs or pidfs file no matter\nwhat mount namespace it lives in so that /proc/<pid>/ns/<ns> and pidfds\ncan be bind mounted. If we create a bind-mount stack of mount namespaces\nfile descriptors the kernel will copy them irrespective of their\nancestoral relationship to the mount namespace in question:\n\n 151 146 0:7 net:[4026531833] /tmp/nrc/y rw - nsfs nsfs rw\n 152 151 0:7 mnt:[4026532293] /tmp/nrc/y rw - nsfs nsfs rw\n\nMount 152 is a mount of the mount namespace file of mount namespace\n4026532293 inside mount namespace 4026532293. That namespace and every\nmount in it are leaked... All it takes is a process in an older mount\nnamespace that stacks the file and repeating it leaks without limit:\n\n after control: Shmem: 380 kB\n child: mount(/proc/self/fd/6, MS_BIND|MS_REC): ok\n after cycle: Shmem: 65916 kB\n\ndo_move_mount() runs check_for_nsfs_mounts() over a detached tree for\nexactly that reason. Do the same for the copy before it is grafted."}], "id": "CVE-2026-98989", "lastModified": "2026-10-23T13:17:20.863", "metrics": {}, "published": "2026-10-23T13:17:20.863", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/37a82f400efa4d263542a5fa41755b21057f1e5d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a0ba48256f5dff6f75a45f8ce39fe57f21df1022"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/c640a01a78e42302879006ed7b7d5a9a943ba815"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[e149ed2b805fefdccf7ccdfc19eca22fdd4514ac,a0ba48256f5dff6f75a45f8ce39fe57f21df1022)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[e149ed2b805fefdccf7ccdfc19eca22fdd4514ac,37a82f400efa4d263542a5fa41755b21057f1e5d)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[e149ed2b805fefdccf7ccdfc19eca22fdd4514ac,c640a01a78e42302879006ed7b7d5a9a943ba815)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "3.19"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,3.19)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.57,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.11,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3,*]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[e149ed2b805fefdccf7ccdfc19eca22fdd4514ac,a0ba48256f5dff6f75a45f8ce39fe57f21df1022)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[e149ed2b805fefdccf7ccdfc19eca22fdd4514ac,37a82f400efa4d263542a5fa41755b21057f1e5d)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[e149ed2b805fefdccf7ccdfc19eca22fdd4514ac,c640a01a78e42302879006ed7b7d5a9a943ba815)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "3.19"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,3.19)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.57,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.11,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3,*]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-10-23T17:00:15.616224+00:00", "updated": "2026-10-23T19:30:17.796816+00:00", "vendors": ["linux", "linux$PRODUCT$linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-770"]}