{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-47316 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2021-47316 yet. Limit exposure of the affected software until one is available.","what":"CVE-2021-47316 is a high-severity vulnerability in Linux kernel, published on 21 May 2024. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2021-47316 and fix it if it is affected.\n\nWhat it is: CVE-2021-47316 is a high-severity vulnerability in Linux kernel, published on 21 May 2024. 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-2021-47316 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-2021-47316/ (Markdown: https://insights.sbomify.com/CVE-2021-47316/index.md)","id":"CVE-2021-47316","markdown":"https://insights.sbomify.com/CVE-2021-47316/index.md","name":"CVE-2021-47316","record":{"aliases":["GHSA-x95x-w6hq-mwxc","UBUNTU-CVE-2021-47316"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Linux kernel NFS","requires_auth":"none","summary":"A NULL pointer dereference in the Linux kernel NFS server can cause a denial of service when handling specific error cases in ACL encoding.","user_interaction":"not_required","vuln_class":"null_dereference"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"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":[{"id":"CWE-476","name":"NULL Pointer Dereference"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix NULL dereference in nfs3svc_encode_getaclres\n\nIn error cases the dentry may be NULL.\n\nBefore 20798dfe249a, the encoder also checked dentry and\nd_really_is_positive(dentry), but that looks like overkill to me--zero\nstatus should be enough to guarantee a positive dentry.\n\nThis isn't the first time we've seen an error-case NULL dereference\nhidden in the initialization of a local variable in an xdr encoder.  But\nI went back through the other recent rewrites and didn't spot any\nsimilar bugs.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":false,"headline":"nfsd: fix NULL dereference in nfs3svc_encode_getaclres","id":"CVE-2021-47316","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"null_dereference","year":"2021"},"n_packages":0,"n_references":3,"next":{"headline":"powerpc/bpf: Fix detecting BPF atomic instructions","id":"CVE-2021-47317"},"packages":[],"prev":{"headline":"memory: fsl_ifc: fix leak of IO mapping on probe failure","id":"CVE-2021-47315"},"products":["Linux"],"published":"2024-05-21","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":"2026-10-14","vendors":["Linux"]},"summary":"A NULL pointer dereference in the Linux kernel NFS server can cause a denial of service when handling specific error cases in ACL encoding.","url":"https://insights.sbomify.com/CVE-2021-47316/"}