{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2025-37856 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-37856 is a high-severity vulnerability in Linux kernel, published on 9 May 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-2025-37856 and fix it if it is affected.\n\nWhat it is: CVE-2025-37856 is a high-severity vulnerability in Linux kernel, published on 9 May 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-2025-37856 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-2025-37856/ (Markdown: https://insights.sbomify.com/CVE-2025-37856/index.md)","id":"CVE-2025-37856","markdown":"https://insights.sbomify.com/CVE-2025-37856/index.md","name":"CVE-2025-37856","record":{"aliases":["AZL-62738","AZL-70141","BELL-CVE-2025-37856","DEBIAN-CVE-2025-37856","GHSA-ppp2-86mr-9vh3","ROOT-OS-DEBIAN-11-CVE-2025-37856","ROOT-OS-DEBIAN-12-CVE-2025-37856","ROOT-OS-UBUNTU-2204-CVE-2025-37856","ROOT-OS-UBUNTU-2404-CVE-2025-37856","UBUNTU-CVE-2025-37856"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A race condition in the Linux kernel's btrfs filesystem can cause a refcount underflow and kernel warning, potentially leading to denial of service.","user_interaction":"not_required","vuln_class":"race_condition"},"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":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: harden block_group::bg_list against list_del() races\n\nAs far as I can tell, these calls of list_del_init() on bg_list cannot\nrun concurrently with btrfs_mark_bg_unused() or btrfs_mark_bg_to_reclaim(),\nas they are in transaction error paths and situations where the block\ngroup is readonly.\n\nHowever, if there is any chance at all of racing with mark_bg_unused(),\nor a different future user of bg_list, better to be safe than sorry.\n\nOtherwise we risk the following interleaving (bg_list refcount in parens)\n\nT1 (some random op)                       T2 (btrfs_mark_bg_unused)\n                                        !list_empty(\u0026bg-\u003ebg_list); (1)\nlist_del_init(\u0026bg-\u003ebg_list); (1)\n                                        list_move_tail (1)\nbtrfs_put_block_group (0)\n                                        btrfs_delete_unused_bgs\n                                             bg = list_first_entry\n                                             list_del_init(\u0026bg-\u003ebg_list);\n                                             btrfs_put_block_group(bg); (-1)\n\nUltimately, this results in a broken ref count that hits zero one deref\nearly and the real final deref underflows the refcount, resulting in a WARNING.","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":"btrfs: harden block_group::bg_list against list_del() races","id":"CVE-2025-37856","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"race_condition","year":"2025"},"n_packages":0,"n_references":5,"next":{"headline":"scsi: st: Fix array overflow in st_setup()","id":"CVE-2025-37857"},"packages":[],"prev":{"headline":"drm/amd/display: Guard Possible Null Pointer Dereference","id":"CVE-2025-37855"},"products":["Linux"],"published":"2025-05-09","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":"2026-10-21","vendors":["Linux"]},"summary":"A race condition in the Linux kernel's btrfs filesystem can cause a refcount underflow and kernel warning, potentially leading to denial of service.","url":"https://insights.sbomify.com/CVE-2025-37856/"}