{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2025-40212 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-40212 is a critical use after free vulnerability in Linux, published on 24 Nov 2025. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2025-40212 and fix it if it is affected.\n\nWhat it is: CVE-2025-40212 is a critical use after free vulnerability in Linux, published on 24 Nov 2025. 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-2025-40212 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-2025-40212/ (Markdown: https://insights.sbomify.com/CVE-2025-40212/index.md)","id":"CVE-2025-40212","markdown":"https://insights.sbomify.com/CVE-2025-40212/index.md","name":"CVE-2025-40212","record":{"aliases":["BELL-CVE-2025-40212","DEBIAN-CVE-2025-40212","GHSA-cjm8-jghh-jmq3","ROOT-OS-DEBIAN-13-CVE-2025-40212","SUSE-SU-2026:20148-1","SUSE-SU-2026:20163-1","SUSE-SU-2026:20165-1","UBUNTU-CVE-2025-40212"],"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 refcount leak in the Linux kernel NFS server allows a malicious client to trigger a use-after-free, potentially causing a denial of service.","user_interaction":"not_required","vuln_class":"use_after_free"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":9.8,"severity":"critical","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix refcount leak in nfsd_set_fh_dentry()\n\nnfsd exports a \"pseudo root filesystem\" which is used by NFSv4 to find\nthe various exported filesystems using LOOKUP requests from a known root\nfilehandle.  NFSv3 uses the MOUNT protocol to find those exported\nfilesystems and so is not given access to the pseudo root filesystem.\n\nIf a v3 (or v2) client uses a filehandle from that filesystem,\nnfsd_set_fh_dentry() will report an error, but still stores the export\nin \"struct svc_fh\" even though it also drops the reference (exp_put()).\nThis means that when fh_put() is called an extra reference will be dropped\nwhich can lead to use-after-free and possible denial of service.\n\nNormal NFS usage will not provide a pseudo-root filehandle to a v3\nclient.  This bug can only be triggered by the client synthesising an\nincorrect filehandle.\n\nTo fix this we move the assignments to the svc_fh later, after all\npossible error cases have been detected.","ecosystems":["SUSE:Linux Enterprise Server 16.0","SUSE:Linux Enterprise Server for SAP applications 16.0","SUSE:Linux Micro 6.2"],"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 refcount leak in nfsd_set_fh_dentry()","id":"CVE-2025-40212","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"use_after_free","year":"2025"},"n_packages":4,"n_references":3,"next":{"headline":"Bluetooth: MGMT: fix crash in set_mesh_sync and set_mesh_complete","id":"CVE-2025-40213"},"packages":[{"ecosystem":"SUSE:Linux Enterprise Server 16.0","fixed":["2-160000.1.1"],"introduced":["0"],"last_affected":[],"package":"kernel-livepatch-SLE16_Update_2","purl":"pkg:rpm/suse/kernel-livepatch-SLE16_Update_2\u0026distro=SUSE%20Linux%20Enterprise%20Server%2016.0","source":"SUSE-SU-2026:20148-1"},{"ecosystem":"SUSE:Linux Enterprise Server for SAP applications 16.0","fixed":["2-160000.1.1"],"introduced":["0"],"last_affected":[],"package":"kernel-livepatch-SLE16_Update_2","purl":"pkg:rpm/suse/kernel-livepatch-SLE16_Update_2\u0026distro=SUSE%20Linux%20Enterprise%20Server%20for%20SAP%20applications%2016.0","source":"SUSE-SU-2026:20148-1"},{"ecosystem":"SUSE:Linux Micro 6.2","fixed":["2-160000.1.1"],"introduced":["0"],"last_affected":[],"package":"kernel-livepatch-SLE16-RT_Update_2","purl":"pkg:rpm/suse/kernel-livepatch-SLE16-RT_Update_2\u0026distro=SUSE%20Linux%20Micro%206.2","source":"SUSE-SU-2026:20165-1"},{"ecosystem":"SUSE:Linux Micro 6.2","fixed":["2-160000.1.1"],"introduced":["0"],"last_affected":[],"package":"kernel-livepatch-SLE16_Update_2","purl":"pkg:rpm/suse/kernel-livepatch-SLE16_Update_2\u0026distro=SUSE%20Linux%20Micro%206.2","source":"SUSE-SU-2026:20163-1"}],"prev":{"headline":"ACPI: video: Fix use-after-free in acpi_video_switch_brightness()","id":"CVE-2025-40211"},"products":["Linux"],"published":"2025-11-24","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"SUSE","prefix":"SUSE"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-08-05","vendors":["Linux"]},"summary":"A refcount leak in the Linux kernel NFS server allows a malicious client to trigger a use-after-free, potentially causing a denial of service.","url":"https://insights.sbomify.com/CVE-2025-40212/"}