{"id":"CVE-2026-80920","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-80920","generatedAt":"2026-10-28T05:59:01.695Z","title":"In the Linux kernel, the following vulnerability has been resolved: io_uring: defer eventfd signaling when queued from a wakeup handler io_req_local_work_add() signals the CQ ring eventfd inline when it is the one to push the first entry onto ->work_list.","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring: defer eventfd signaling when queued from a wakeup handler\n\nio_req_local_work_add() signals the CQ ring eventfd inline when it is the\none to push the first entry onto ->work_list. For DEFER_TASKRUN rings that\nadd is frequently done from a waitqueue wakeup handler, where an\narbitrary waitqueue lock is held.\n\neventfd_signal_mask() only refuses to recurse when current->in_eventfd\nis set, but that bit is set by eventfd_signal_mask() itself. If the wake\nchain starts somewhere else, signal goes out inline and can feed back\ninto epoll.\n\nAdd IOU_F_TWQ_IN_WAKE, set it on the task_work add done from the three\nwaitqueue callbacks, and use it to force io_eventfd_signal() down the\nexisting call_rcu_hurry() deferral instead of signaling inline.","published":"2026-09-09T17:17:47.000Z","lastModified":"2026-10-21T13:20:01.000Z","status":"Received","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":null,"cwe":[],"affected":[],"epss":{"score":0.00167,"percentile":0.0588,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"unknown","text":"Not yet scored. NVD analysis is pending; check back once CVSS and EPSS values are published."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/40b6ccf68731809ceb85c6e9f0f8f2ed61c7aa5a","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/9d984451baf768ecd9e1fdad4637b729fcb2c9d5","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b6bb334b0e9348887e3e55e1f494b0c3b8fbf59f","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/cd305ee3633a45fcf5f3a5d83f99f3cb77d87b6e","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d0c240f25e654442a72af5ca021a02165ccce638","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e22f4494cc9487d326e5e3067f33dea7c1e442b2","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-80920","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}