{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-89766", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.764Z", "datePublished": "2026-09-11T19:47:06.597Z", "dateUpdated": "2026-10-19T08:52:19.816Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:52:19.816Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\npidfd: hold exec_update_lock around namespace ioctl\n\nThe PIDFD_GET_*_NAMESPACE ioctls in pidfd_ioctl() perform a filesystem\ncredentials ptrace access check before handing out a namespace file\ndescriptor. The accompanying comment states that the code \"mirrors nsfs\nbehavior\", but, unlike the corresponding procfs paths, it does so without\nholding the target task's exec_update_lock.\n\nproc_ns_get_link() and proc_ns_readlink() both take exec_update_lock for\nreading around the ptrace check and the namespace lookup, so that the\ncredentials used for the access decision match those of the task when its\nnamespace is read. Without it, a caller can pass the check against the\ntarget's old credentials and then read the namespace after the target has\nexecve()'d a setuid binary and committed new credentials -- accessing\nnamespace information it should have been denied.\n\nHold exec_update_lock for reading around the ptrace check and the\nnamespace lookup so that pidfd truly mirrors nsfs behavior, as the comment\nalready claims. open_namespace() itself runs outside the lock: once a\nnamespace reference is obtained it carries its own refcount and is opened\nwith the caller's own credentials, so a concurrent execve() on the target\ncan no longer affect the outcome." } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/pidfs.c" ], "versions": [ { "version": "5b08bd408534bfb3a7cf5778da5b27d4e4fffe12", "lessThan": "bac2f1913a216677c2c220d7bb352dd0330065ca", "status": "affected", "versionType": "git" }, { "version": "5b08bd408534bfb3a7cf5778da5b27d4e4fffe12", "lessThan": "cf24ce48d60225fdbee68ed2058763a1fd172ff3", "status": "affected", "versionType": "git" }, { "version": "5b08bd408534bfb3a7cf5778da5b27d4e4fffe12", "lessThan": "e89318aa8629969e86548b05e7c19283af3f0efb", "status": "affected", "versionType": "git" }, { "version": "5b08bd408534bfb3a7cf5778da5b27d4e4fffe12", "lessThan": "9688a46802939da28f00cb40e8129615d5d4af39", "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/pidfs.c" ], "versions": [ { "version": "6.11", "status": "affected" }, { "version": "0", "lessThan": "6.11", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.112", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.51", "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": "6.11", "versionEndExcluding": "6.12.112" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "6.18.51" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "7.2.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/bac2f1913a216677c2c220d7bb352dd0330065ca" }, { "url": "https://git.kernel.org/stable/c/cf24ce48d60225fdbee68ed2058763a1fd172ff3" }, { "url": "https://git.kernel.org/stable/c/e89318aa8629969e86548b05e7c19283af3f0efb" }, { "url": "https://git.kernel.org/stable/c/9688a46802939da28f00cb40e8129615d5d4af39" } ], "title": "pidfd: hold exec_update_lock around namespace ioctl", "x_generator": { "engine": "bippy-1.2.0" } } } }