{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2025-21811 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-21811 is a high-severity use after free vulnerability in Linux kernel, published on 27 Feb 2025. 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-2025-21811 and fix it if it is affected.\n\nWhat it is: CVE-2025-21811 is a high-severity use after free vulnerability in Linux kernel, published on 27 Feb 2025. 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-2025-21811 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-2025-21811/ (Markdown: https://insights.sbomify.com/CVE-2025-21811/index.md)","id":"CVE-2025-21811","markdown":"https://insights.sbomify.com/CVE-2025-21811/index.md","name":"CVE-2025-21811","record":{"aliases":["BELL-CVE-2025-21811","DEBIAN-CVE-2025-21811","GHSA-j2gc-738w-q744","ROOT-OS-UBUNTU-2404-CVE-2025-21811","UBUNTU-CVE-2025-21811"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["code_execution","privilege_escalation"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A race condition in the nilfs2 filesystem allows attackers to trigger a use-after-free, potentially leading to code execution or privilege escalation.","user_interaction":"not_required","vuln_class":"use_after_free"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":7.8,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-416","name":"Use After Free"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnilfs2: protect access to buffers with no active references\n\nnilfs_lookup_dirty_data_buffers(), which iterates through the buffers\nattached to dirty data folios/pages, accesses the attached buffers without\nlocking the folios/pages.\n\nFor data cache, nilfs_clear_folio_dirty() may be called asynchronously\nwhen the file system degenerates to read only, so\nnilfs_lookup_dirty_data_buffers() still has the potential to cause use\nafter free issues when buffers lose the protection of their dirty state\nmidway due to this asynchronous clearing and are unintentionally freed by\ntry_to_free_buffers().\n\nEliminate this race issue by adjusting the lock section in this function.","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":"nilfs2: protect access to buffers with no active references","id":"CVE-2025-21811","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"use_after_free","year":"2025"},"n_packages":0,"n_references":8,"next":{"headline":"ax25: rcu protect dev-\u003eax25_ptr","id":"CVE-2025-21812"},"packages":[],"prev":{"headline":"driver core: class: Fix wild pointer dereferences in API class_dev_iter_next()","id":"CVE-2025-21810"},"products":["Linux"],"published":"2025-02-27","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":"total"},"state":"PUBLISHED","updated":"2026-08-05","vendors":["Linux"]},"summary":"A race condition in the nilfs2 filesystem allows attackers to trigger a use-after-free, potentially leading to code execution or privilege escalation.","url":"https://insights.sbomify.com/CVE-2025-21811/"}