{"id":"CVE-2026-89518","title":"kernel: sched_ext: Fix this_rq() assumptions in dispatch kfuncs (CVE-2026-89518)","summary":"A flaw was found in the Linux kernel's `sched_ext` component. Under core scheduling, incorrect assumptions in dispatch kfuncs regarding `this_rq()` can lead to a deadlock. This occurs when an `rq` lock is acquired on a CPU different from t…","severity":"medium","cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cvssSource":"vendor","cwe":"CWE-833","vendor":"Red Hat","product":"Linux","affected":["Linux >= 4c95380701f58b8112f0b891de8d160e4199e19d < 6d1890d3c6137ab523799765ae2de62cc05f116d","Linux >= 4c95380701f58b8112f0b891de8d160e4199e19d < 3dd52416e44a70bc993adb96d2e0d71b9ea21359","Linux 6.19"],"published":"2026-09-11","updated":"2026-09-14","sourceUpdated":"2026-09-14T08:39:29+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89518.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89518.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89518"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532018"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89518"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89518"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89518.mbox"},{"url":"https://git.kernel.org/stable/c/6d1890d3c6137ab523799765ae2de62cc05f116d"},{"url":"https://git.kernel.org/stable/c/3dd52416e44a70bc993adb96d2e0d71b9ea21359"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.00189,"epssPercentile":0.08814,"ingestedAt":"2026-09-14T11:11:19.887Z","slug":"CVE-2026-89518","body":"## Overview\n\nA flaw was found in the Linux kernel's `sched_ext` component. Under core scheduling, incorrect assumptions in dispatch kfuncs regarding `this_rq()` can lead to a deadlock. This occurs when an `rq` lock is acquired on a CPU different from the dispatched `rq`'s, potentially causing the system to become unresponsive. This vulnerability could result in a Denial of Service (DoS).\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · updated 2026-09-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89518.json)\n\n**kernel: sched_ext: Fix this_rq() assumptions in dispatch kfuncs** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-14.\n\nNot affected:\n\n- Red Hat Enterprise Linux 10\n- Red Hat Enterprise Linux 6\n- Red Hat Enterprise Linux 7\n- Red Hat Enterprise Linux 8\n- Red Hat Enterprise Linux 9\n- Red Hat OpenShift Container Platform 4\n\n## Remediation\n\nRefer to the advisory for fix availability.","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":202804,"id":"CVE-2026-89518","ts":1789403724492,"field":"cvss","old":null,"new":"5.5"},{"seq":202803,"id":"CVE-2026-89518","ts":1789403724492,"field":"severity","old":"none","new":"medium"},{"seq":109616,"id":"CVE-2026-89518","ts":1789183732660,"field":"cvss","old":null,"new":"4.7"},{"seq":109615,"id":"CVE-2026-89518","ts":1789183732660,"field":"severity","old":"none","new":"medium"}]}