{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-45920 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-45920 is a high-severity vulnerability in Linux kernel, published on 27 May 2026. 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-2026-45920 and fix it if it is affected.\n\nWhat it is: CVE-2026-45920 is a high-severity vulnerability in Linux kernel, published on 27 May 2026. 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-2026-45920 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-2026-45920/ (Markdown: https://insights.sbomify.com/CVE-2026-45920/index.md)","id":"CVE-2026-45920","markdown":"https://insights.sbomify.com/CVE-2026-45920/index.md","name":"CVE-2026-45920","record":{"aliases":["BELL-CVE-2026-45920","DEBIAN-CVE-2026-45920","GHSA-r62x-r6m8-28mx","ROOT-OS-UBUNTU-2204-CVE-2026-45920","ROOT-OS-UBUNTU-2404-CVE-2026-45920","UBUNTU-CVE-2026-45920"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel ext4","requires_auth":"low_privilege","summary":"A double decrement bug in the Linux kernel ext4 filesystem can trigger a kernel warning and potential instability during filesystem shutdown operations.","user_interaction":"not_required","vuln_class":"other"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":7.8,"severity":"high","source":"nvd","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-415","name":"Double Free"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix dirtyclusters double decrement on fs shutdown\n\nfstests test generic/388 occasionally reproduces a warning in\next4_put_super() associated with the dirty clusters count:\n\n  WARNING: CPU: 7 PID: 76064 at fs/ext4/super.c:1324 ext4_put_super+0x48c/0x590 [ext4]\n\nTracing the failure shows that the warning fires due to an\ns_dirtyclusters_counter value of -1. IOW, this appears to be a\nspurious decrement as opposed to some sort of leak. Further tracing\nof the dirty cluster count deltas and an LLM scan of the resulting\noutput identified the cause as a double decrement in the error path\nbetween ext4_mb_mark_diskspace_used() and the caller\next4_mb_new_blocks().\n\nFirst, note that generic/388 is a shutdown vs. fsstress test and so\nproduces a random set of operations and shutdown injections. In the\nproblematic case, the shutdown triggers an error return from the\next4_handle_dirty_metadata() call(s) made from\next4_mb_mark_context(). The changed value is non-zero at this point,\nso ext4_mb_mark_diskspace_used() does not exit after the error\nbubbles up from ext4_mb_mark_context(). Instead, the former\ndecrements both cluster counters and returns the error up to\next4_mb_new_blocks(). The latter falls into the !ar-\u003elen out path\nwhich decrements the dirty clusters counter a second time, creating\nthe inconsistency.\n\nTo avoid this problem and simplify ownership of the cluster\nreservation in this codepath, lift the counter reduction to a single\nplace in the caller. This makes it more clear that\next4_mb_new_blocks() is responsible for acquiring cluster\nreservation (via ext4_claim_free_clusters()) in the !delalloc case\nas well as releasing it, regardless of whether it ends up consumed\nor returned due to failure.","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":"ext4: fix dirtyclusters double decrement on fs shutdown","id":"CVE-2026-45920","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"other","year":"2026"},"n_packages":0,"n_references":8,"next":{"headline":"mtd: parsers: Fix memory leak in mtd_parser_tplink_safeloader_parse()","id":"CVE-2026-45921"},"packages":[],"prev":{"headline":"sched/rt: Skip currently executing CPU in rto_next_cpu()","id":"CVE-2026-45919"},"products":["Linux"],"published":"2026-05-27","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":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-05-27","vendors":["Linux"]},"summary":"A double decrement bug in the Linux kernel ext4 filesystem can trigger a kernel warning and potential instability during filesystem shutdown operations.","url":"https://insights.sbomify.com/CVE-2026-45920/"}