{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2025-21646 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-21646 is a high-severity denial of service vulnerability in Linux kernel, published on 19 Jan 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-2025-21646 and fix it if it is affected.\n\nWhat it is: CVE-2025-21646 is a high-severity denial of service vulnerability in Linux kernel, published on 19 Jan 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-2025-21646 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-2025-21646/ (Markdown: https://insights.sbomify.com/CVE-2025-21646/index.md)","id":"CVE-2025-21646","markdown":"https://insights.sbomify.com/CVE-2025-21646/index.md","name":"CVE-2025-21646","record":{"aliases":["BELL-CVE-2025-21646","DEBIAN-CVE-2025-21646","GHSA-qwq3-wccv-85hw","UBUNTU-CVE-2025-21646"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Linux kernel AFS","requires_auth":"none","summary":"A flaw in the Linux kernel AFS filesystem allows a local attacker to trigger a kernel warning and potential denial of service by using a cell name exceeding the procfs filename limit.","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":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\nafs: Fix the maximum cell name length\n\nThe kafs filesystem limits the maximum length of a cell to 256 bytes, but a\nproblem occurs if someone actually does that: kafs tries to create a\ndirectory under /proc/net/afs/ with the name of the cell, but that fails\nwith a warning:\n\n        WARNING: CPU: 0 PID: 9 at fs/proc/generic.c:405\n\nbecause procfs limits the maximum filename length to 255.\n\nHowever, the DNS limits the maximum lookup length and, by extension, the\nmaximum cell name, to 255 less two (length count and trailing NUL).\n\nFix this by limiting the maximum acceptable cellname length to 253.  This\nalso allows us to be sure we can create the \"/afs/.\u003ccell\u003e/\" mountpoint too.\n\nFurther, split the YFS VL record cell name maximum to be the 256 allowed by\nthe protocol and ignore the record retrieved by YFSVL.GetCellName if it\nexceeds 253.","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":"afs: Fix the maximum cell name length","id":"CVE-2025-21646","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"denial_of_service","year":"2025"},"n_packages":0,"n_references":6,"next":{"headline":"sched: sch_cake: add bounds checks to host bulk flow fairness counts","id":"CVE-2025-21647"},"packages":[],"prev":{"headline":"platform/x86/amd/pmc: Only disable IRQ1 wakeup where i8042 actually enabled it","id":"CVE-2025-21645"},"products":["Linux"],"published":"2025-01-19","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":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-08-05","vendors":["Linux"]},"summary":"A flaw in the Linux kernel AFS filesystem allows a local attacker to trigger a kernel warning and potential denial of service by using a cell name exceeding the procfs filename limit.","url":"https://insights.sbomify.com/CVE-2025-21646/"}