CVE-2021-47603

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2021-47603", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-05-24T15:11:00.736Z", "datePublished": "2024-06-19T14:54:02.988Z", "dateUpdated": "2026-05-23T15:20:18.864Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-23T15:20:18.864Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\naudit: improve robustness of the audit queue handling\n\nIf the audit daemon were ever to get stuck in a stopped state the\nkernel's kauditd_thread() could get blocked attempting to send audit\nrecords to the userspace audit daemon. With the kernel thread\nblocked it is possible that the audit queue could grow unbounded as\ncertain audit record generating events must be exempt from the queue\nlimits else the system enter a deadlock state.\n\nThis patch resolves this problem by lowering the kernel thread's\nsocket sending timeout from MAX_SCHEDULE_TIMEOUT to HZ/10 and tweaks\nthe kauditd_send_queue() function to better manage the various audit\nqueues when connection problems occur between the kernel and the\naudit daemon. With this patch, the backlog may temporarily grow\nbeyond the defined limits when the audit daemon is stopped and the\nsystem is under heavy audit pressure, but kauditd_thread() will\ncontinue to make progress and drain the queues as it would for other\nconnection problems. For example, with the audit daemon put into a\nstopped state and the system configured to audit every syscall it\nwas still possible to shutdown the system without a kernel panic,\ndeadlock, etc.; granted, the system was slow to shutdown but that is\nto be expected given the extreme pressure of recording every syscall.\n\nThe timeout value of HZ/10 was chosen primarily through\nexperimentation and this developer's \"gut feeling\". There is likely\nno one perfect value, but as this scenario is limited in scope (root\nprivileges would be needed to send SIGSTOP to the audit daemon), it\nis likely not worth exposing this as a tunable at present. This can\nalways be done at a later date if it proves necessary."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/audit.c"], "versions": [{"version": "5b52330bbfe63b3305765354d6046c9f7f89c011", "lessThan": "75fdb751f84727d614deea0571a1490c3225d83a", "status": "affected", "versionType": "git"}, {"version": "5b52330bbfe63b3305765354d6046c9f7f89c011", "lessThan": "8389f50ceb854cb437fefb9330d5024ed3c7c1f5", "status": "affected", "versionType": "git"}, {"version": "5b52330bbfe63b3305765354d6046c9f7f89c011", "lessThan": "0d3277eabd542fb662be23696e5ec9f390d688e1", "status": "affected", "versionType": "git"}, {"version": "5b52330bbfe63b3305765354d6046c9f7f89c011", "lessThan": "4cc6badff97f74d0fce65f9784b5df3b64e4250b", "status": "affected", "versionType": "git"}, {"version": "5b52330bbfe63b3305765354d6046c9f7f89c011", "lessThan": "a5f4d17daf2e6cd7c1d9676b476147f6b4ac53f2", "status": "affected", "versionType": "git"}, {"version": "5b52330bbfe63b3305765354d6046c9f7f89c011", "lessThan": "f4b3ee3c85551d2d343a3ba159304066523f730f", "status": "affected", "versionType": "git"}, {"version": "a0c48115cd2343231585f2f5e609b2ac9aa4e0af", "status": "affected", "versionType": "git"}, {"version": "4.10.7", "lessThan": "4.11", "status": "affected", "versionType": "semver"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/audit.c"], "versions": [{"version": "4.11", "status": "affected"}, {"version": "0", "lessThan": "4.11", "status": "unaffected", "versionType": "semver"}, {"version": "4.14.259", "lessThanOrEqual": "4.14.*", "status": "unaffected", "versionType": "semver"}, {"version": "4.19.222", "lessThanOrEqual": "4.19.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.4.168", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.88", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.11", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.16", "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": "4.11", "versionEndExcluding": "4.14.259"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "4.19.222"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "5.4.168"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "5.10.88"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "5.15.11"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "5.16"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.10.7"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/75fdb751f84727d614deea0571a1490c3225d83a"}, {"url": "https://git.kernel.org/stable/c/8389f50ceb854cb437fefb9330d5024ed3c7c1f5"}, {"url": "https://git.kernel.org/stable/c/0d3277eabd542fb662be23696e5ec9f390d688e1"}, {"url": "https://git.kernel.org/stable/c/4cc6badff97f74d0fce65f9784b5df3b64e4250b"}, {"url": "https://git.kernel.org/stable/c/a5f4d17daf2e6cd7c1d9676b476147f6b4ac53f2"}, {"url": "https://git.kernel.org/stable/c/f4b3ee3c85551d2d343a3ba159304066523f730f"}], "title": "audit: improve robustness of the audit queue handling", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2024-06-20T13:46:15.530530Z", "id": "CVE-2021-47603", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-06-20T13:46:23.577Z"}}, {"providerMetadata": {"orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-04T05:47:40.675Z"}, "title": "CVE Program Container", "references": [{"url": "https://git.kernel.org/stable/c/75fdb751f84727d614deea0571a1490c3225d83a", "tags": ["x_transferred"]}, {"url": "https://git.kernel.org/stable/c/8389f50ceb854cb437fefb9330d5024ed3c7c1f5", "tags": ["x_transferred"]}, {"url": "https://git.kernel.org/stable/c/0d3277eabd542fb662be23696e5ec9f390d688e1", "tags": ["x_transferred"]}, {"url": "https://git.kernel.org/stable/c/4cc6badff97f74d0fce65f9784b5df3b64e4250b", "tags": ["x_transferred"]}, {"url": "https://git.kernel.org/stable/c/a5f4d17daf2e6cd7c1d9676b476147f6b4ac53f2", "tags": ["x_transferred"]}, {"url": "https://git.kernel.org/stable/c/f4b3ee3c85551d2d343a3ba159304066523f730f", "tags": ["x_transferred"]}]}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CVE Program Container", "references": [{"url": "https://git.kernel.org/stable/c/75fdb751f84727d614deea0571a1490c3225d83a", "tags": ["x_transferred"]}, {"url": "https://git.kernel.org/stable/c/8389f50ceb854cb437fefb9330d5024ed3c7c1f5", "tags": ["x_transferred"]}, {"url": "https://git.kernel.org/stable/c/0d3277eabd542fb662be23696e5ec9f390d688e1", "tags": ["x_transferred"]}, {"url": "https://git.kernel.org/stable/c/4cc6badff97f74d0fce65f9784b5df3b64e4250b", "tags": ["x_transferred"]}, {"url": "https://git.kernel.org/stable/c/a5f4d17daf2e6cd7c1d9676b476147f6b4ac53f2", "tags": ["x_transferred"]}, {"url": "https://git.kernel.org/stable/c/f4b3ee3c85551d2d343a3ba159304066523f730f", "tags": ["x_transferred"]}], "providerMetadata": {"orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-04T05:47:40.675Z"}}, {"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2021-47603", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2024-06-20T13:46:15.530530Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-06-20T13:46:19.921Z"}}], "cna": {"title": "audit: improve robustness of the audit queue handling", "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "5b52330bbfe63b3305765354d6046c9f7f89c011", "lessThan": "75fdb751f84727d614deea0571a1490c3225d83a", "versionType": "git"}, {"status": "affected", "version": "5b52330bbfe63b3305765354d6046c9f7f89c011", "lessThan": "8389f50ceb854cb437fefb9330d5024ed3c7c1f5", "versionType": "git"}, {"status": "affected", "version": "5b52330bbfe63b3305765354d6046c9f7f89c011", "lessThan": "0d3277eabd542fb662be23696e5ec9f390d688e1", "versionType": "git"}, {"status": "affected", "version": "5b52330bbfe63b3305765354d6046c9f7f89c011", "lessThan": "4cc6badff97f74d0fce65f9784b5df3b64e4250b", "versionType": "git"}, {"status": "affected", "version": "5b52330bbfe63b3305765354d6046c9f7f89c011", "lessThan": "a5f4d17daf2e6cd7c1d9676b476147f6b4ac53f2", "versionType": "git"}, {"status": "affected", "version": "5b52330bbfe63b3305765354d6046c9f7f89c011", "lessThan": "f4b3ee3c85551d2d343a3ba159304066523f730f", "versionType": "git"}, {"status": "affected", "version": "a0c48115cd2343231585f2f5e609b2ac9aa4e0af", "versionType": "git"}, {"status": "affected", "version": "4.10.7", "lessThan": "4.11", "versionType": "semver"}], "programFiles": ["kernel/audit.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "4.11"}, {"status": "unaffected", "version": "0", "lessThan": "4.11", "versionType": "semver"}, {"status": "unaffected", "version": "4.14.259", "versionType": "semver", "lessThanOrEqual": "4.14.*"}, {"status": "unaffected", "version": "4.19.222", "versionType": "semver", "lessThanOrEqual": "4.19.*"}, {"status": "unaffected", "version": "5.4.168", "versionType": "semver", "lessThanOrEqual": "5.4.*"}, {"status": "unaffected", "version": "5.10.88", "versionType": "semver", "lessThanOrEqual": "5.10.*"}, {"status": "unaffected", "version": "5.15.11", "versionType": "semver", "lessThanOrEqual": "5.15.*"}, {"status": "unaffected", "version": "5.16", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["kernel/audit.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/75fdb751f84727d614deea0571a1490c3225d83a"}, {"url": "https://git.kernel.org/stable/c/8389f50ceb854cb437fefb9330d5024ed3c7c1f5"}, {"url": "https://git.kernel.org/stable/c/0d3277eabd542fb662be23696e5ec9f390d688e1"}, {"url": "https://git.kernel.org/stable/c/4cc6badff97f74d0fce65f9784b5df3b64e4250b"}, {"url": "https://git.kernel.org/stable/c/a5f4d17daf2e6cd7c1d9676b476147f6b4ac53f2"}, {"url": "https://git.kernel.org/stable/c/f4b3ee3c85551d2d343a3ba159304066523f730f"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\naudit: improve robustness of the audit queue handling\n\nIf the audit daemon were ever to get stuck in a stopped state the\nkernel's kauditd_thread() could get blocked attempting to send audit\nrecords to the userspace audit daemon. With the kernel thread\nblocked it is possible that the audit queue could grow unbounded as\ncertain audit record generating events must be exempt from the queue\nlimits else the system enter a deadlock state.\n\nThis patch resolves this problem by lowering the kernel thread's\nsocket sending timeout from MAX_SCHEDULE_TIMEOUT to HZ/10 and tweaks\nthe kauditd_send_queue() function to better manage the various audit\nqueues when connection problems occur between the kernel and the\naudit daemon. With this patch, the backlog may temporarily grow\nbeyond the defined limits when the audit daemon is stopped and the\nsystem is under heavy audit pressure, but kauditd_thread() will\ncontinue to make progress and drain the queues as it would for other\nconnection problems. For example, with the audit daemon put into a\nstopped state and the system configured to audit every syscall it\nwas still possible to shutdown the system without a kernel panic,\ndeadlock, etc.; granted, the system was slow to shutdown but that is\nto be expected given the extreme pressure of recording every syscall.\n\nThe timeout value of HZ/10 was chosen primarily through\nexperimentation and this developer's \"gut feeling\". There is likely\nno one perfect value, but as this scenario is limited in scope (root\nprivileges would be needed to send SIGSTOP to the audit daemon), it\nis likely not worth exposing this as a tunable at present. This can\nalways be done at a later date if it proves necessary."}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "4.14.259", "versionStartIncluding": "4.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "4.19.222", "versionStartIncluding": "4.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.4.168", "versionStartIncluding": "4.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.10.88", "versionStartIncluding": "4.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.15.11", "versionStartIncluding": "4.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.16", "versionStartIncluding": "4.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionStartIncluding": "4.10.7"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-23T15:20:18.864Z"}}}, "cveMetadata": {"cveId": "CVE-2021-47603", "state": "PUBLISHED", "dateUpdated": "2026-05-23T15:20:18.864Z", "dateReserved": "2024-05-24T15:11:00.736Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2024-06-19T14:54:02.988Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["kernel/audit.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "75fdb751f84727d614deea0571a1490c3225d83a", "status": "affected", "version": "5b52330bbfe63b3305765354d6046c9f7f89c011", "versionType": "git"}, {"lessThan": "8389f50ceb854cb437fefb9330d5024ed3c7c1f5", "status": "affected", "version": "5b52330bbfe63b3305765354d6046c9f7f89c011", "versionType": "git"}, {"lessThan": "0d3277eabd542fb662be23696e5ec9f390d688e1", "status": "affected", "version": "5b52330bbfe63b3305765354d6046c9f7f89c011", "versionType": "git"}, {"lessThan": "4cc6badff97f74d0fce65f9784b5df3b64e4250b", "status": "affected", "version": "5b52330bbfe63b3305765354d6046c9f7f89c011", "versionType": "git"}, {"lessThan": "a5f4d17daf2e6cd7c1d9676b476147f6b4ac53f2", "status": "affected", "version": "5b52330bbfe63b3305765354d6046c9f7f89c011", "versionType": "git"}, {"lessThan": "f4b3ee3c85551d2d343a3ba159304066523f730f", "status": "affected", "version": "5b52330bbfe63b3305765354d6046c9f7f89c011", "versionType": "git"}, {"status": "affected", "version": "a0c48115cd2343231585f2f5e609b2ac9aa4e0af", "versionType": "git"}, {"lessThan": "4.11", "status": "affected", "version": "4.10.7", "versionType": "semver"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["kernel/audit.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "4.11"}, {"lessThan": "4.11", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "4.14.*", "status": "unaffected", "version": "4.14.259", "versionType": "semver"}, {"lessThanOrEqual": "4.19.*", "status": "unaffected", "version": "4.19.222", "versionType": "semver"}, {"lessThanOrEqual": "5.4.*", "status": "unaffected", "version": "5.4.168", "versionType": "semver"}, {"lessThanOrEqual": "5.10.*", "status": "unaffected", "version": "5.10.88", "versionType": "semver"}, {"lessThanOrEqual": "5.15.*", "status": "unaffected", "version": "5.15.11", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "5.16", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "002AFF57-621F-4DFC-BA33-323006B9E2CB", "versionEndExcluding": "4.11", "versionStartIncluding": "4.10.7", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "F52B82B4-2759-4BAE-914F-9BCD47B64147", "versionEndExcluding": "4.14.259", "versionStartIncluding": "4.11", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "2D0D89BC-6CF8-4BFB-8C91-472348052528", "versionEndExcluding": "4.19.222", "versionStartIncluding": "4.15", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "195EBAA1-4CCE-4898-9351-F4A0DBCAA022", "versionEndExcluding": "5.4.168", "versionStartIncluding": "4.20", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "A657B2D0-5B9D-42BE-A3BF-228DBC1B057C", "versionEndExcluding": "5.10.88", "versionStartIncluding": "5.5", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "11274E95-438A-449A-B100-01B2B0046669", "versionEndExcluding": "5.15.11", "versionStartIncluding": "5.11", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc1:*:*:*:*:*:*", "matchCriteriaId": "357AA433-37E8-4323-BFB2-3038D6E4B414", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc2:*:*:*:*:*:*", "matchCriteriaId": "A73429BA-C2D9-4D0C-A75F-06A1CA8B3983", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc3:*:*:*:*:*:*", "matchCriteriaId": "F621B5E3-E99D-49E7-90B9-EC3B77C95383", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc4:*:*:*:*:*:*", "matchCriteriaId": "F7BFDCAA-1650-49AA-8462-407DD593F94F", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc5:*:*:*:*:*:*", "matchCriteriaId": "6EC9882F-866D-4ACB-8FBC-213D8D8436C8", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\naudit: improve robustness of the audit queue handling\n\nIf the audit daemon were ever to get stuck in a stopped state the\nkernel's kauditd_thread() could get blocked attempting to send audit\nrecords to the userspace audit daemon. With the kernel thread\nblocked it is possible that the audit queue could grow unbounded as\ncertain audit record generating events must be exempt from the queue\nlimits else the system enter a deadlock state.\n\nThis patch resolves this problem by lowering the kernel thread's\nsocket sending timeout from MAX_SCHEDULE_TIMEOUT to HZ/10 and tweaks\nthe kauditd_send_queue() function to better manage the various audit\nqueues when connection problems occur between the kernel and the\naudit daemon. With this patch, the backlog may temporarily grow\nbeyond the defined limits when the audit daemon is stopped and the\nsystem is under heavy audit pressure, but kauditd_thread() will\ncontinue to make progress and drain the queues as it would for other\nconnection problems. For example, with the audit daemon put into a\nstopped state and the system configured to audit every syscall it\nwas still possible to shutdown the system without a kernel panic,\ndeadlock, etc.; granted, the system was slow to shutdown but that is\nto be expected given the extreme pressure of recording every syscall.\n\nThe timeout value of HZ/10 was chosen primarily through\nexperimentation and this developer's \"gut feeling\". There is likely\nno one perfect value, but as this scenario is limited in scope (root\nprivileges would be needed to send SIGSTOP to the audit daemon), it\nis likely not worth exposing this as a tunable at present. This can\nalways be done at a later date if it proves necessary."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: auditor\u00eda: mejora la solidez del manejo de la cola de auditor\u00eda. Si el daemon de auditor\u00eda alguna vez se atascara en un estado detenido, kauditd_thread() del kernel podr\u00eda bloquearse al intentar enviar registros de auditor\u00eda al espacio de usuario. daemon de auditor\u00eda. Con el subproceso del n\u00facleo bloqueado, es posible que la cola de auditor\u00eda crezca sin l\u00edmites, ya que ciertos eventos que generan registros de auditor\u00eda deben estar exentos de los l\u00edmites de la cola, de lo contrario, el sistema entrar\u00e1 en un estado de bloqueo. Este parche resuelve este problema reduciendo el tiempo de espera de env\u00edo del socket del subproceso del n\u00facleo de MAX_SCHEDULE_TIMEOUT a HZ/10 y modifica la funci\u00f3n kauditd_send_queue() para gestionar mejor las distintas colas de auditor\u00eda cuando se producen problemas de conexi\u00f3n entre el n\u00facleo y el daemon de auditor\u00eda. Con este parche, el trabajo pendiente puede crecer temporalmente m\u00e1s all\u00e1 de los l\u00edmites definidos cuando se detiene el daemon de auditor\u00eda y el sistema est\u00e1 bajo una fuerte presi\u00f3n de auditor\u00eda, pero kauditd_thread() continuar\u00e1 progresando y drenando las colas como lo har\u00eda con otros problemas de conexi\u00f3n. Por ejemplo, con el daemon de auditor\u00eda en estado detenido y el sistema configurado para auditar cada llamada al sistema, a\u00fan era posible apagar el sistema sin p\u00e1nico en el kernel, interbloqueo, etc.; Por supuesto, el sistema tard\u00f3 en cerrarse, pero eso es de esperarse dada la presi\u00f3n extrema de registrar cada llamada al sistema. El valor de tiempo de espera de HZ/10 se eligi\u00f3 principalmente a trav\u00e9s de la experimentaci\u00f3n y el \"instinto\" de este desarrollador. Probablemente no exista un valor perfecto, pero como este escenario tiene un alcance limitado (se necesitar\u00edan privilegios de root para enviar SIGSTOP al daemon de auditor\u00eda), probablemente no valga la pena exponerlo como un ajuste ajustable en este momento. Esto siempre se puede hacer en una fecha posterior si resulta necesario."}], "id": "CVE-2021-47603", "lastModified": "2026-06-17T04:18:08.613", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 4.4, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "HIGH", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 0.8, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2021-47603", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2024-06-20T13:46:15.530530Z", "version": "2.0.3"}}]}, "published": "2024-06-19T15:15:54.863", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/0d3277eabd542fb662be23696e5ec9f390d688e1"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/4cc6badff97f74d0fce65f9784b5df3b64e4250b"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/75fdb751f84727d614deea0571a1490c3225d83a"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/8389f50ceb854cb437fefb9330d5024ed3c7c1f5"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/a5f4d17daf2e6cd7c1d9676b476147f6b4ac53f2"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/f4b3ee3c85551d2d343a3ba159304066523f730f"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/0d3277eabd542fb662be23696e5ec9f390d688e1"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/4cc6badff97f74d0fce65f9784b5df3b64e4250b"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/75fdb751f84727d614deea0571a1490c3225d83a"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/8389f50ceb854cb437fefb9330d5024ed3c7c1f5"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/a5f4d17daf2e6cd7c1d9676b476147f6b4ac53f2"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/f4b3ee3c85551d2d343a3ba159304066523f730f"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-667"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: audit: improve robustness of the audit queue handling", "id": "2293223", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2293223"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.4", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-833", "details": ["In the Linux kernel, the following vulnerability has been resolved:\naudit: improve robustness of the audit queue handling\nIf the audit daemon were ever to get stuck in a stopped state the\nkernel's kauditd_thread() could get blocked attempting to send audit\nrecords to the userspace audit daemon. With the kernel thread\nblocked it is possible that the audit queue could grow unbounded as\ncertain audit record generating events must be exempt from the queue\nlimits else the system enter a deadlock state.\nThis patch resolves this problem by lowering the kernel thread's\nsocket sending timeout from MAX_SCHEDULE_TIMEOUT to HZ/10 and tweaks\nthe kauditd_send_queue() function to better manage the various audit\nqueues when connection problems occur between the kernel and the\naudit daemon. With this patch, the backlog may temporarily grow\nbeyond the defined limits when the audit daemon is stopped and the\nsystem is under heavy audit pressure, but kauditd_thread() will\ncontinue to make progress and drain the queues as it would for other\nconnection problems. For example, with the audit daemon put into a\nstopped state and the system configured to audit every syscall it\nwas still possible to shutdown the system without a kernel panic,\ndeadlock, etc.; granted, the system was slow to shutdown but that is\nto be expected given the extreme pressure of recording every syscall.\nThe timeout value of HZ/10 was chosen primarily through\nexperimentation and this developer's \"gut feeling\". There is likely\nno one perfect value, but as this scenario is limited in scope (root\nprivileges would be needed to send SIGSTOP to the audit daemon), it\nis likely not worth exposing this as a tunable at present. This can\nalways be done at a later date if it proves necessary."], "name": "CVE-2021-47603", "package_state": [{"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": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2024-06-19T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2021-47603\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-47603\nhttps://lore.kernel.org/linux-cve-announce/2024061922-CVE-2021-47603-ec18@gregkh/T"], "threat_severity": "Low"}

{}