CVE-2026-99040

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-99040", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.387Z", "datePublished": "2026-10-23T12:21:59.288Z", "dateUpdated": "2026-10-30T12:41:13.694Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-30T12:41:13.694Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKEYS: Fix add_key() race with keyring restriction\n\n__key_create_or_update() snapshots keyring->restrict_link before taking\nthe destination keyring's semaphore. keyring_restrict() installs a\nrestriction while holding that semaphore.\n\nThis allows a writer to observe no restriction, wait for the keyring\nowner to install a reject-all restriction and return successfully, and\nthen link a key using the stale NULL snapshot. The writer only needs\nwrite permission on the destination keyring.\n\nMove the restrict_link read after __key_link_lock() and\n__key_link_begin(). The read and the subsequent restriction check are\nthen serialized with restriction installation by keyring->sem.\n\nThe race was reproduced on v7.2.8 in 19 executions where restriction\ninstallation returned before the link completed. All 19 linked the key\ndespite the reject-all restriction. With this change, 312 executions\nreached the same ordering and every add_key() call failed with -EPERM.\n\nThe issue was found by manual concurrency analysis assisted by AI-based\nanalysis and independently verified with a QEMU reproducer and kernel\ninstrumentation."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["security/keys/key.c"], "versions": [{"version": "5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c", "lessThan": "24806fc9bca28fa1433bf938d1424dcb45d80e50", "status": "affected", "versionType": "git"}, {"version": "5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c", "lessThan": "9a5c2700336878465a630804a2d21864f22eca9c", "status": "affected", "versionType": "git"}, {"version": "5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c", "lessThan": "b3e404550dc2b7f3d4bb64b1da8005a1fa9a798d", "status": "affected", "versionType": "git"}, {"version": "5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c", "lessThan": "305f1828b871dd46bf41addeb6f11d2c162dcb25", "status": "affected", "versionType": "git"}, {"version": "5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c", "lessThan": "f99399b48e3edd6851fac34cd329bab9f1f33baf", "status": "affected", "versionType": "git"}, {"version": "5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c", "lessThan": "11516a0c402a6c1fa52254aa70d8d65fb921e59e", "status": "affected", "versionType": "git"}, {"version": "5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c", "lessThan": "da0b595d8e6e2dd798f6e34e09dc51a13b888514", "status": "affected", "versionType": "git"}, {"version": "5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c", "lessThan": "dd3ea3fcba7c75493760cdbccd35f029597e8d5e", "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/keys/key.c"], "versions": [{"version": "4.7", "status": "affected"}, {"version": "0", "lessThan": "4.7", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.273", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.224", "lessThanOrEqual": "5.15.*", "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": "6.12.113", "lessThanOrEqual": "6.12.*", "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": "4.7", "versionEndExcluding": "5.10.273"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "5.15.224"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "6.1.191"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "6.6.160"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "6.12.113"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "6.18.57"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "7.2.11"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/24806fc9bca28fa1433bf938d1424dcb45d80e50"}, {"url": "https://git.kernel.org/stable/c/9a5c2700336878465a630804a2d21864f22eca9c"}, {"url": "https://git.kernel.org/stable/c/b3e404550dc2b7f3d4bb64b1da8005a1fa9a798d"}, {"url": "https://git.kernel.org/stable/c/305f1828b871dd46bf41addeb6f11d2c162dcb25"}, {"url": "https://git.kernel.org/stable/c/f99399b48e3edd6851fac34cd329bab9f1f33baf"}, {"url": "https://git.kernel.org/stable/c/11516a0c402a6c1fa52254aa70d8d65fb921e59e"}, {"url": "https://git.kernel.org/stable/c/da0b595d8e6e2dd798f6e34e09dc51a13b888514"}, {"url": "https://git.kernel.org/stable/c/dd3ea3fcba7c75493760cdbccd35f029597e8d5e"}], "title": "KEYS: Fix add_key() race with keyring restriction", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["security/keys/key.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "24806fc9bca28fa1433bf938d1424dcb45d80e50", "status": "affected", "version": "5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c", "versionType": "git"}, {"lessThan": "9a5c2700336878465a630804a2d21864f22eca9c", "status": "affected", "version": "5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c", "versionType": "git"}, {"lessThan": "b3e404550dc2b7f3d4bb64b1da8005a1fa9a798d", "status": "affected", "version": "5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c", "versionType": "git"}, {"lessThan": "305f1828b871dd46bf41addeb6f11d2c162dcb25", "status": "affected", "version": "5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c", "versionType": "git"}, {"lessThan": "f99399b48e3edd6851fac34cd329bab9f1f33baf", "status": "affected", "version": "5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c", "versionType": "git"}, {"lessThan": "11516a0c402a6c1fa52254aa70d8d65fb921e59e", "status": "affected", "version": "5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c", "versionType": "git"}, {"lessThan": "da0b595d8e6e2dd798f6e34e09dc51a13b888514", "status": "affected", "version": "5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c", "versionType": "git"}, {"lessThan": "dd3ea3fcba7c75493760cdbccd35f029597e8d5e", "status": "affected", "version": "5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["security/keys/key.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "4.7"}, {"lessThan": "4.7", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "5.10.*", "status": "unaffected", "version": "5.10.273", "versionType": "semver"}, {"lessThanOrEqual": "5.15.*", "status": "unaffected", "version": "5.15.224", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.191", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.160", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.113", "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\nKEYS: Fix add_key() race with keyring restriction\n\n__key_create_or_update() snapshots keyring->restrict_link before taking\nthe destination keyring's semaphore. keyring_restrict() installs a\nrestriction while holding that semaphore.\n\nThis allows a writer to observe no restriction, wait for the keyring\nowner to install a reject-all restriction and return successfully, and\nthen link a key using the stale NULL snapshot. The writer only needs\nwrite permission on the destination keyring.\n\nMove the restrict_link read after __key_link_lock() and\n__key_link_begin(). The read and the subsequent restriction check are\nthen serialized with restriction installation by keyring->sem.\n\nThe race was reproduced on v7.2.8 in 19 executions where restriction\ninstallation returned before the link completed. All 19 linked the key\ndespite the reject-all restriction. With this change, 312 executions\nreached the same ordering and every add_key() call failed with -EPERM.\n\nThe issue was found by manual concurrency analysis assisted by AI-based\nanalysis and independently verified with a QEMU reproducer and kernel\ninstrumentation."}], "id": "CVE-2026-99040", "lastModified": "2026-10-30T13:21:41.200", "metrics": {}, "published": "2026-10-23T13:17:27.360", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/11516a0c402a6c1fa52254aa70d8d65fb921e59e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/24806fc9bca28fa1433bf938d1424dcb45d80e50"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/305f1828b871dd46bf41addeb6f11d2c162dcb25"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/9a5c2700336878465a630804a2d21864f22eca9c"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/b3e404550dc2b7f3d4bb64b1da8005a1fa9a798d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/da0b595d8e6e2dd798f6e34e09dc51a13b888514"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/dd3ea3fcba7c75493760cdbccd35f029597e8d5e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f99399b48e3edd6851fac34cd329bab9f1f33baf"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: KEYS: Fix add_key() race with keyring restriction", "id": "2559833", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2559833"}, "csaw": false, "cvss3": {"cvss3_base_score": "2.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N", "status": "draft"}, "cwe": "CWE-367", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nKEYS: Fix add_key() race with keyring restriction\n__key_create_or_update() snapshots keyring->restrict_link before taking\nthe destination keyring's semaphore. keyring_restrict() installs a\nrestriction while holding that semaphore.\nThis allows a writer to observe no restriction, wait for the keyring\nowner to install a reject-all restriction and return successfully, and\nthen link a key using the stale NULL snapshot. The writer only needs\nwrite permission on the destination keyring.\nMove the restrict_link read after __key_link_lock() and\n__key_link_begin(). The read and the subsequent restriction check are\nthen serialized with restriction installation by keyring->sem.\nThe race was reproduced on v7.2.8 in 19 executions where restriction\ninstallation returned before the link completed. All 19 linked the key\ndespite the reject-all restriction. With this change, 312 executions\nreached the same ordering and every add_key() call failed with -EPERM.\nThe issue was found by manual concurrency analysis assisted by AI-based\nanalysis and independently verified with a QEMU reproducer and kernel\ninstrumentation.", "A flaw was found in the Linux kernel's key management facility. This vulnerability allows a local user with write access to bypass security controls and add unauthorized keys to a restricted keyring. The issue occurs due to a race condition between key creation and the enforcement of keyring restrictions, allowing a key to be linked using an outdated restriction state."], "name": "CVE-2026-99040", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "openshift/ose-rhel-coreos-8", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "openshift/ose-rhel-coreos-9", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-10-23T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-99040\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-99040\nhttps://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-99040.mbox"], "threat_severity": "Low"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c,305f1828b871dd46bf41addeb6f11d2c162dcb25)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c,f99399b48e3edd6851fac34cd329bab9f1f33baf)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c,11516a0c402a6c1fa52254aa70d8d65fb921e59e)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c,da0b595d8e6e2dd798f6e34e09dc51a13b888514)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c,dd3ea3fcba7c75493760cdbccd35f029597e8d5e)"}}], "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": "4.7"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,4.7)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.160,6.7.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.113,6.13.0)"}}, {"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": "[5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c,305f1828b871dd46bf41addeb6f11d2c162dcb25)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c,f99399b48e3edd6851fac34cd329bab9f1f33baf)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c,11516a0c402a6c1fa52254aa70d8d65fb921e59e)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c,da0b595d8e6e2dd798f6e34e09dc51a13b888514)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5ac7eace2d00eab5ae0e9fdee63e38aee6001f7c,dd3ea3fcba7c75493760cdbccd35f029597e8d5e)"}}], "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": "4.7"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,4.7)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.160,6.7.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.113,6.13.0)"}}, {"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": "2026-10-23T17:00:15.614472+00:00", "updated": "2026-10-29T15:00:22.066917+00:00", "vendors": ["linux", "linux$PRODUCT$linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-362", "CWE-367"]}