{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2025-21860 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-21860 is a low-severity denial of service vulnerability in Linux kernel, published on 12 Mar 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-2025-21860 and fix it if it is affected.\n\nWhat it is: CVE-2025-21860 is a low-severity denial of service vulnerability in Linux kernel, published on 12 Mar 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-2025-21860 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-2025-21860/ (Markdown: https://insights.sbomify.com/CVE-2025-21860/index.md)","id":"CVE-2025-21860","markdown":"https://insights.sbomify.com/CVE-2025-21860/index.md","name":"CVE-2025-21860","record":{"aliases":["BELL-CVE-2025-21860","GHSA-gp26-q8h6-xxgj","UBUNTU-CVE-2025-21860"],"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 logic error in Linux kernel zswap handling causes accounting inconsistencies and kernel warnings, potentially leading to system instability or denial of service.","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":3.3,"severity":"low","source":"nvd","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L","version":"3.1"},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/zswap: fix inconsistency when zswap_store_page() fails\n\nCommit b7c0ccdfbafd (\"mm: zswap: support large folios in zswap_store()\")\nskips charging any zswap entries when it failed to zswap the entire folio.\n\nHowever, when some base pages are zswapped but it failed to zswap the\nentire folio, the zswap operation is rolled back.  When freeing zswap\nentries for those pages, zswap_entry_free() uncharges the zswap entries\nthat were not previously charged, causing zswap charging to become\ninconsistent.\n\nThis inconsistency triggers two warnings with following steps:\n  # On a machine with 64GiB of RAM and 36GiB of zswap\n  $ stress-ng --bigheap 2 # wait until the OOM-killer kills stress-ng\n  $ sudo reboot\n\n  The two warnings are:\n    in mm/memcontrol.c:163, function obj_cgroup_release():\n      WARN_ON_ONCE(nr_bytes \u0026 (PAGE_SIZE - 1));\n\n    in mm/page_counter.c:60, function page_counter_cancel():\n      if (WARN_ONCE(new \u003c 0, \"page_counter underflow: %ld nr_pages=%lu\\n\",\n\t  new, nr_pages))\n\nzswap_stored_pages also becomes inconsistent in the same way.\n\nAs suggested by Kanchana, increment zswap_stored_pages and charge zswap\nentries within zswap_store_page() when it succeeds.  This way,\nzswap_entry_free() will decrement the counter and uncharge the entries\nwhen it failed to zswap the entire folio.\n\nWhile this could potentially be optimized by batching objcg charging and\nincrementing the counter, let's focus on fixing the bug this time and\nleave the optimization for later after some evaluation.\n\nAfter resolving the inconsistency, the warnings disappear.\n\n[42.hyeyoo@gmail.com: refactor zswap_store_page()]","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":"mm/zswap: fix inconsistency when zswap_store_page() fails","id":"CVE-2025-21860","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":2,"next":{"headline":"mm/migrate_device: don't add folio to be freed to LRU in migrate_device_finalize()","id":"CVE-2025-21861"},"packages":[],"prev":{"headline":"USB: gadget: f_midi: f_midi_complete to call queue_work","id":"CVE-2025-21859"},"products":["Linux"],"published":"2025-03-12","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":"2026-05-11","vendors":["Linux"]},"summary":"A logic error in Linux kernel zswap handling causes accounting inconsistencies and kernel warnings, potentially leading to system instability or denial of service.","url":"https://insights.sbomify.com/CVE-2025-21860/"}