{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2025-40327 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-40327 is a denial of service vulnerability in Linux, published on 9 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-2025-40327 and fix it if it is affected.\n\nWhat it is: CVE-2025-40327 is a denial of service vulnerability in Linux, published on 9 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-2025-40327 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-2025-40327/ (Markdown: https://insights.sbomify.com/CVE-2025-40327/index.md)","id":"CVE-2025-40327","markdown":"https://insights.sbomify.com/CVE-2025-40327/index.md","name":"CVE-2025-40327","record":{"aliases":["BELL-CVE-2025-40327","DEBIAN-CVE-2025-40327","GHSA-px83-f67g-j9g9","UBUNTU-CVE-2025-40327"],"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 local attacker can cause a system hang in the Linux kernel by triggering a deadlock in the perf subsystem via cpu-clock events.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":null,"severity":null,"source":null,"vector":null,"version":null},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nperf/core: Fix system hang caused by cpu-clock usage\n\ncpu-clock usage by the async-profiler tool can trigger a system hang,\nwhich got bisected back to the following commit by Octavia Togami:\n\n  18dbcbfabfff (\"perf: Fix the POLL_HUP delivery breakage\") causes this issue\n\nThe root cause of the hang is that cpu-clock is a special type of SW\nevent which relies on hrtimers. The __perf_event_overflow() callback\nis invoked from the hrtimer handler for cpu-clock events, and\n__perf_event_overflow() tries to call cpu_clock_event_stop()\nto stop the event, which calls htimer_cancel() to cancel the hrtimer.\n\nBut that's a recursion into the hrtimer code from a hrtimer handler,\nwhich (unsurprisingly) deadlocks.\n\nTo fix this bug, use hrtimer_try_to_cancel() instead, and set\nthe PERF_HES_STOPPED flag, which causes perf_swevent_hrtimer()\nto stop the event once it sees the PERF_HES_STOPPED flag.\n\n[ mingo: Fixed the comments and improved the changelog. ]","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":"perf/core: Fix system hang caused by cpu-clock usage","id":"CVE-2025-40327","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"denial_of_service","year":"2025"},"n_packages":0,"n_references":2,"next":{"headline":"smb: client: fix potential UAF in smb2_close_cached_fid()","id":"CVE-2025-40328"},"packages":[],"prev":{"headline":"NFSD: Define actions for the new time_deleg FATTR4 attributes","id":"CVE-2025-40326"},"products":["Linux"],"published":"2025-12-09","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-05-23","vendors":["Linux"]},"summary":"A local attacker can cause a system hang in the Linux kernel by triggering a deadlock in the perf subsystem via cpu-clock events.","url":"https://insights.sbomify.com/CVE-2025-40327/"}