{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-89679 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-89679 is a high-severity vulnerability in Linux, published on 11 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-89679 and fix it if it is affected.\n\nWhat it is: CVE-2026-89679 is a high-severity vulnerability in Linux, published on 11 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-89679 in the wild and no public exploit code.\n\nAffected product: Linux. 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-2026-89679/ (Markdown: https://insights.sbomify.com/CVE-2026-89679/index.md)","id":"CVE-2026-89679","markdown":"https://insights.sbomify.com/CVE-2026-89679/index.md","name":"CVE-2026-89679","record":{"aliases":["BELL-CVE-2026-89679","DEBIAN-CVE-2026-89679","GHSA-8j83-qm9m-m369","UBUNTU-CVE-2026-89679"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Linux kernel NFS server","requires_auth":"none","summary":"A remote attacker can cause a kernel crash in the Linux NFS server by sending a specially crafted SETATTR request with a special stateid.","user_interaction":"not_required","vuln_class":"null_dereference"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":7.5,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix null dereference in nfsd4_setattr for deleg timestamp attrs\n\nWhen a SETATTR request includes FATTR4_WORD2_TIME_DELEG_ACCESS or\nFATTR4_WORD2_TIME_DELEG_MODIFY in the attribute bitmap, nfsd4_setattr()\nsets deleg_attrs=true and calls nfs4_preprocess_stateid_op() to validate\nthe stateid.\n\nIf the client supplies the NFSv4 \"one stateid\" (all-0xFF bytes),\ncheck_special_stateids() returns nfs_ok without populating the output\nnfs4_stid pointer, because the special-stateid path in\nnfs4_preprocess_stateid_op() jumps to done: with s==NULL, and the\n\"if (s)\" block that would set *cstid is skipped. The local variable `st`\nremains NULL.\n\nBack in nfsd4_setattr(), the if (deleg_attrs) block then unconditionally\ndereferences st-\u003esc_type (at offset 4 from NULL), causing a kernel oops.\n\nThis is remotely triggerable by any NFSv4 client: send COMPOUND [PUTROOTFH,\nSETATTR(ONE_STATEID, {bmval2=FATTR4_WORD2_TIME_DELEG_ACCESS, ...})].\nNo authentication, delegation, or prior state is required.\n\nFix by adding a NULL check before the dereference. A special stateid is\nnot a delegation stateid, so the existing nfserr_bad_stateid return value\nis already correct; we only need to guard the pointer dereference itself.","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 null dereference in nfsd4_setattr for deleg timestamp attrs","id":"CVE-2026-89679","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"null_dereference","year":"2026"},"n_packages":0,"n_references":3,"next":{"headline":"nfsd: fix nfsd_file leak on inter-server COPY setup failure","id":"CVE-2026-89680"},"packages":[],"prev":{"headline":"nfsd: fix partial-write detection in nfsd_direct_write","id":"CVE-2026-89678"},"products":["Linux"],"published":"2026-09-11","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-10-19","vendors":["Linux"]},"summary":"A remote attacker can cause a kernel crash in the Linux NFS server by sending a specially crafted SETATTR request with a special stateid.","url":"https://insights.sbomify.com/CVE-2026-89679/"}