{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2024-26629 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2024-26629 is a medium-severity vulnerability in Linux kernel, published on 13 Mar 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-2024-26629 and fix it if it is affected.\n\nWhat it is: CVE-2024-26629 is a medium-severity vulnerability in Linux kernel, published on 13 Mar 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-2024-26629 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-2024-26629/ (Markdown: https://insights.sbomify.com/CVE-2024-26629/index.md)","id":"CVE-2024-26629","markdown":"https://insights.sbomify.com/CVE-2024-26629/index.md","name":"CVE-2024-26629","record":{"aliases":["BELL-CVE-2024-26629","DEBIAN-CVE-2024-26629","GHSA-x66g-5578-7px9","UBUNTU-CVE-2024-26629"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel NFS server","requires_auth":"low_privilege","summary":"A race condition in the Linux kernel NFS server can cause incorrect lock release errors, leading to client-server state desynchronization and potential denial of service.","user_interaction":"not_required","vuln_class":"race_condition"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":5.5,"severity":"medium","source":"nvd","vector":"CVSS:3.1/AV:L/AC:L/PR:L/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\nnfsd: fix RELEASE_LOCKOWNER\n\nThe test on so_count in nfsd4_release_lockowner() is nonsense and\nharmful.  Revert to using check_for_locks(), changing that to not sleep.\n\nFirst: harmful.\nAs is documented in the kdoc comment for nfsd4_release_lockowner(), the\ntest on so_count can transiently return a false positive resulting in a\nreturn of NFS4ERR_LOCKS_HELD when in fact no locks are held.  This is\nclearly a protocol violation and with the Linux NFS client it can cause\nincorrect behaviour.\n\nIf RELEASE_LOCKOWNER is sent while some other thread is still\nprocessing a LOCK request which failed because, at the time that request\nwas received, the given owner held a conflicting lock, then the nfsd\nthread processing that LOCK request can hold a reference (conflock) to\nthe lock owner that causes nfsd4_release_lockowner() to return an\nincorrect error.\n\nThe Linux NFS client ignores that NFS4ERR_LOCKS_HELD error because it\nnever sends NFS4_RELEASE_LOCKOWNER without first releasing any locks, so\nit knows that the error is impossible.  It assumes the lock owner was in\nfact released so it feels free to use the same lock owner identifier in\nsome later locking request.\n\nWhen it does reuse a lock owner identifier for which a previous RELEASE\nfailed, it will naturally use a lock_seqid of zero.  However the server,\nwhich didn't release the lock owner, will expect a larger lock_seqid and\nso will respond with NFS4ERR_BAD_SEQID.\n\nSo clearly it is harmful to allow a false positive, which testing\nso_count allows.\n\nThe test is nonsense because ... well... it doesn't mean anything.\n\nso_count is the sum of three different counts.\n1/ the set of states listed on so_stateids\n2/ the set of active vfs locks owned by any of those states\n3/ various transient counts such as for conflicting locks.\n\nWhen it is tested against '2' it is clear that one of these is the\ntransient reference obtained by find_lockowner_str_locked().  It is not\nclear what the other one is expected to be.\n\nIn practice, the count is often 2 because there is precisely one state\non so_stateids.  If there were more, this would fail.\n\nIn my testing I see two circumstances when RELEASE_LOCKOWNER is called.\nIn one case, CLOSE is called before RELEASE_LOCKOWNER.  That results in\nall the lock states being removed, and so the lockowner being discarded\n(it is removed when there are no more references which usually happens\nwhen the lock state is discarded).  When nfsd4_release_lockowner() finds\nthat the lock owner doesn't exist, it returns success.\n\nThe other case shows an so_count of '2' and precisely one state listed\nin so_stateid.  It appears that the Linux client uses a separate lock\nowner for each file resulting in one lock state per lock owner, so this\ntest on '2' is safe.  For another client it might not be safe.\n\nSo this patch changes check_for_locks() to use the (newish)\nfind_any_file_locked() so that it doesn't take a reference on the\nnfs4_file and so never calls nfsd_file_put(), and so never sleeps.  With\nthis check is it safe to restore the use of check_for_locks() rather\nthan testing so_count against the mysterious '2'.","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":"nfsd: fix RELEASE_LOCKOWNER","id":"CVE-2024-26629","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"race_condition","year":"2024"},"n_packages":0,"n_references":7,"next":{"headline":"mm: cachestat: fix folio read-after-free in cache walk","id":"CVE-2024-26630"},"packages":[],"prev":{"headline":"This CVE ID has been rejected or withdrawn by its CVE Numbering Authority.","id":"CVE-2024-26628"},"products":["Linux"],"published":"2024-03-13","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":"2026-10-15","vendors":["Linux"]},"summary":"A race condition in the Linux kernel NFS server can cause incorrect lock release errors, leading to client-server state desynchronization and potential denial of service.","url":"https://insights.sbomify.com/CVE-2024-26629/"}