{"id":"EM-20261102-L868","url":"https://cyber.eventmonitor.net/incident/EM-20261102-L868/","type":"cve","title":"Linux Kernel Vulnerability (CVE-2026-99227)","subtitle":"CVE-2026-99227","subject":"CVE-2026-99227","status":"Developing","severity":"high","affected":[],"headline":null,"born":"2026-11-02T16:17:47.420Z","firstSignal":"2026-11-02T16:06:36.000Z","lastSignal":"2026-11-02T16:17:47.420Z","updated":"2026-11-04T14:43:58.877Z","revision":1,"life":[{"status":"Born","at":"2026-11-02T16:17:47.420Z","why":"second independent source: C6 NVD CVE API 2.0"},{"status":"Developing","at":"2026-11-02T16:17:47.420Z","why":"signals keep joining"}],"changeLog":[{"at":"2026-11-02T16:06:36.000Z","what":"First signal: C41 Red Hat Security Data"},{"at":"2026-11-02T16:17:47.420Z","what":"Born: second source, C6 NVD CVE API 2.0. Page EM-20261102-L868 created."}],"stages":[{"name":"Disclosed","at":"2026-11-02T16:17:47.420Z","detail":"C6 NVD published"},{"name":"Scored","at":"2026-11-02T16:17:47.420Z","detail":"CVSS 7.8 · EPSS 0.1%"},{"name":"Exploited","at":null,"detail":"No exploitation reported"},{"name":"Advisories","at":null,"detail":"None yet"},{"name":"Vendor Response","at":"2026-11-02T16:06:36.000Z","detail":"C41 published"},{"name":"Resolved","at":null,"detail":"After 14 quiet days"}],"signals":[{"at":"2026-11-02T16:06:36.000Z","source":"C41","sourceName":"Red Hat Security Data","role":"Vendor","severity":3,"title":"Red Hat: CVE-2026-99227 (important)","text":"kernel: kernel: Privilege escalation via reference counter wrap in io_uring","url":"https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-99227.json"},{"at":"2026-11-02T16:17:47.420Z","source":"C6","sourceName":"NVD CVE API 2.0","role":"Database","severity":3,"title":"CVE-2026-99227 (CVSS 7.8)","text":"In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/waitid: prevent cancel reference wrap\n\nio_waitid packs the cancellation state into bit 31 of ->refs and uses\nbits 30:0 as a 31-bit reference counter:\n\n  #define IO_WAITID_CANCEL_FLAG BIT(31)\n  #define IO_WAITID_REF_MASK    GENMASK(30, 0)\n\n__io_waitid_cancel() marks a request canceled, then increments the low\nbits of ->refs to claim completion ownership. When another path owns the\nrequest, the increment remains even though cancellation returns false.\nThe request remains discoverable by cancellation, so repeated failed","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-99227"}],"crowd":[],"reference":{"nvd":{"published":"2026-11-02T16:17:47.420","score":7.8,"severity":"HIGH","desc":"In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/waitid: prevent cancel reference wrap\n\nio_waitid packs the cancellation state into bit 31 of ->refs and uses\nbits 30:0 as a 31-bit reference counter:\n\n  #define IO_WAITID_CANCEL_FLAG BIT(31)\n  #define IO_WAITID_REF_MASK   ","product":"","seen":1793803438877},"kev":null,"epss":{"epss":0.0012,"pct":0.01845,"at":1793803438877},"p0":false},"mergedInto":null,"publisher":"Event Monitor Cyber"}