{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2025-40307 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-40307 is a high-severity denial of service vulnerability in Linux, published on 8 Dec 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-2025-40307 and fix it if it is affected.\n\nWhat it is: CVE-2025-40307 is a high-severity denial of service vulnerability in Linux, published on 8 Dec 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-2025-40307 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-2025-40307/ (Markdown: https://insights.sbomify.com/CVE-2025-40307/index.md)","id":"CVE-2025-40307","markdown":"https://insights.sbomify.com/CVE-2025-40307/index.md","name":"CVE-2025-40307","record":{"aliases":["BELL-CVE-2025-40307","DEBIAN-CVE-2025-40307","GHSA-9mhh-qxx8-wc58","ROOT-OS-DEBIAN-11-CVE-2025-40307","ROOT-OS-DEBIAN-12-CVE-2025-40307","ROOT-OS-DEBIAN-13-CVE-2025-40307","ROOT-OS-UBUNTU-2204-CVE-2025-40307","ROOT-OS-UBUNTU-2404-CVE-2025-40307","UBUNTU-CVE-2025-40307"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["data_modify","denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel exFAT","requires_auth":"low_privilege","summary":"A missing validation in the Linux kernel exFAT filesystem allows attackers to corrupt allocation bitmaps, leading to data loss and potential denial of service.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"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":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nexfat: validate cluster allocation bits of the allocation bitmap\n\nsyzbot created an exfat image with cluster bits not set for the allocation\nbitmap. exfat-fs reads and uses the allocation bitmap without checking\nthis. The problem is that if the start cluster of the allocation bitmap\nis 6, cluster 6 can be allocated when creating a directory with mkdir.\nexfat zeros out this cluster in exfat_mkdir, which can delete existing\nentries. This can reallocate the allocated entries. In addition,\nthe allocation bitmap is also zeroed out, so cluster 6 can be reallocated.\nThis patch adds exfat_test_bitmap_range to validate that clusters used for\nthe allocation bitmap are correctly marked as in-use.","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":"exfat: validate cluster allocation bits of the allocation bitmap","id":"CVE-2025-40307","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"denial_of_service","year":"2025"},"n_packages":0,"n_references":5,"next":{"headline":"Bluetooth: bcsp: receive data only if registered","id":"CVE-2025-40308"},"packages":[],"prev":{"headline":"orangefs: fix xattr related buffer overflow...","id":"CVE-2025-40306"},"products":["Linux"],"published":"2025-12-08","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":"no","exploitation":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-10-15","vendors":["Linux"]},"summary":"A missing validation in the Linux kernel exFAT filesystem allows attackers to corrupt allocation bitmaps, leading to data loss and potential denial of service.","url":"https://insights.sbomify.com/CVE-2025-40307/"}