{"id":"CVE-2026-89516","title":"kernel: sched_ext: Don't BUG_ON a destroyed DSQ in process_deferred_reenq_users (CVE-2026-89516)","summary":"A flaw was found in the Linux kernel's `sched_ext` component. When a Deferred Scheduling Queue (DSQ) is destroyed, a pending deferred re-enqueue (DRU) operation might still attempt to access the destroyed DSQ. This can lead to a `BUG_ON` c…","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-825","vendor":"Red Hat","product":"Red Hat OpenShift Container Platform 4","affected":["openshift_container_platform 4"],"published":"2026-09-11","updated":"2026-09-18","sourceUpdated":"2026-09-18T21:34:35+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89516.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89516.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89516"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532093"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89516"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89516"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89516.mbox"},{"url":"https://git.kernel.org/stable/c/c480961a1e790b46ffd8c20c4b6754d65ec6572d"},{"url":"https://git.kernel.org/stable/c/8d8dd8ae89eaa78b37fc85528e926029f5facbdf"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.00162,"epssPercentile":0.05857,"ingestedAt":"2026-09-14T11:11:19.887Z","slug":"CVE-2026-89516","body":"## Overview\n\nA flaw was found in the Linux kernel's `sched_ext` component. When a Deferred Scheduling Queue (DSQ) is destroyed, a pending deferred re-enqueue (DRU) operation might still attempt to access the destroyed DSQ. This can lead to a `BUG_ON` condition, causing a kernel panic and resulting in a Denial of Service (DoS) for the system.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · updated 2026-09-18 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89516.json)\n\n**kernel: sched_ext: Don't BUG_ON a destroyed DSQ in process_deferred_reenq_users** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-18.\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":206936,"id":"CVE-2026-89516","ts":1789749708336,"field":"cvss","old":null,"new":"5.5"},{"seq":206935,"id":"CVE-2026-89516","ts":1789749708336,"field":"severity","old":"none","new":"medium"},{"seq":147716,"id":"CVE-2026-89516","ts":1789270211997,"field":"cvss","old":null,"new":"4.1"},{"seq":147715,"id":"CVE-2026-89516","ts":1789270211997,"field":"severity","old":"none","new":"medium"},{"seq":109472,"id":"CVE-2026-89516","ts":1789183732047,"field":"cvss","old":null,"new":"4.1"},{"seq":109471,"id":"CVE-2026-89516","ts":1789183732047,"field":"severity","old":"none","new":"medium"}]}