{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-47603 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2021-47603 is a medium-severity denial of service vulnerability in Linux kernel, published on 19 Jun 2024. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2021-47603 and fix it if it is affected.\n\nWhat it is: CVE-2021-47603 is a medium-severity denial of service vulnerability in Linux kernel, published on 19 Jun 2024. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2021-47603 in the wild and no public exploit code.\n\nAffected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2021-47603/ (Markdown: https://insights.sbomify.com/CVE-2021-47603/index.md)","id":"CVE-2021-47603","markdown":"https://insights.sbomify.com/CVE-2021-47603/index.md","name":"CVE-2021-47603","record":{"aliases":["DEBIAN-CVE-2021-47603","GHSA-xfpp-3cjf-2x3v","UBUNTU-CVE-2021-47603"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":true,"product_category":"Linux kernel","requires_auth":"high_privilege","summary":"A local attacker with root privileges can cause a denial of service by stopping the audit daemon, leading to unbounded kernel queue growth and system hangs.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":4.4,"severity":"medium","source":"nvd","vector":"CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-667","name":"Improper Locking"}],"description":"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.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"audit: improve robustness of the audit queue handling","id":"CVE-2021-47603","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"denial_of_service","year":"2021"},"n_packages":0,"n_references":6,"next":{"headline":"vduse: check that offset is within bounds in get_config()","id":"CVE-2021-47604"},"packages":[],"prev":{"headline":"mac80211: track only QoS data frames for admission control","id":"CVE-2021-47602"},"products":["Linux"],"published":"2024-06-19","related":[{"cvss_score":8.8,"headline":"Linux Kernel Out-of-Bounds Write","id":"CVE-2026-53266","kev_date_added":"2026-09-18","published":"2026-06-25"},{"cvss_score":8.8,"headline":"Linux Kernel Improper Input Validation","id":"CVE-2013-6282","kev_date_added":"2022-09-15","published":"2013-11-19"},{"cvss_score":8.4,"headline":"Linux Kernel Heap-Based Buffer Overflow","id":"CVE-2022-0185","kev_date_added":"2024-08-21","published":"2022-02-11"},{"cvss_score":8.4,"headline":"Linux Kernel Privilege Escalation","id":"CVE-2013-2094","kev_date_added":"2022-09-15","published":"2013-05-14"},{"cvss_score":7.8,"headline":"Linux Kernel Unspecified","id":"CVE-2026-53362","kev_date_added":"2026-08-27","published":"2026-07-04"},{"cvss_score":7.8,"headline":"Linux Kernel Missing Initialization of a Variable","id":"CVE-2026-46300","kev_date_added":"2026-10-28","published":"2026-05-23"},{"cvss_score":7.8,"headline":"Linux Kernel Race Condition","id":"CVE-2025-39964","kev_date_added":"2026-09-18","published":"2025-10-13"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-05-23","vendors":["Linux"]},"summary":"A local attacker with root privileges can cause a denial of service by stopping the audit daemon, leading to unbounded kernel queue growth and system hangs.","url":"https://insights.sbomify.com/CVE-2021-47603/"}