{"id":"CVE-2026-98864","title":"kernel: sched_ext: Wait for SCX_OPSS_DISPATCHING before reenqueueing a task (CVE-2026-98864)","summary":"A flaw was found in the Linux kernel's extensible scheduler (sched_ext) subsystem. A race condition occurs when a task is re-enqueued before a prior dispatch operation has completed, allowing internal scheduling states to be improperly ove…","severity":"medium","cvss":4.7,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","cvssSource":"vendor","cwe":"CWE-366","vendor":"Red Hat","product":"Linux","affected":["Linux >= ebf1ccff79c43f860cbd2f9d6cfab9a462d0cb2d < 43457bf6550044c40bd6d3fcdf9ea66f5a55d139","Linux >= ebf1ccff79c43f860cbd2f9d6cfab9a462d0cb2d < 7de9a6fb44eae4f05e68c805d58b9c618815adfa","Linux 7.1"],"published":"2026-10-18","updated":"2026-10-24","sourceUpdated":"2026-10-24T06:56:08+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98864.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98864.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-98864"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2555198"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98864"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98864"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98864.mbox"},{"url":"https://git.kernel.org/stable/c/43457bf6550044c40bd6d3fcdf9ea66f5a55d139"},{"url":"https://git.kernel.org/stable/c/7de9a6fb44eae4f05e68c805d58b9c618815adfa"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.00159,"epssPercentile":0.04971,"ingestedAt":"2026-10-18T16:47:32.459Z","slug":"CVE-2026-98864","body":"## Overview\n\nA flaw was found in the Linux kernel's extensible scheduler (sched_ext) subsystem. A race condition occurs when a task is re-enqueued before a prior dispatch operation has completed, allowing internal scheduling states to be improperly overwritten. A local user could trigger this flaw to cause subsequent task dispatches to be dropped, leading to stalled processes and a denial of service (DoS).\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · updated 2026-10-24 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98864.json)\n\n**kernel: sched_ext: Wait for SCX_OPSS_DISPATCHING before reenqueueing a task** — rated Moderate by Red Hat. Released 2026-10-18, updated 2026-10-24.\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":26,"depthScoreParts":{"impact":25.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":228526,"id":"CVE-2026-98864","ts":1792844774567,"field":"cvss","old":null,"new":"4.7"},{"seq":228525,"id":"CVE-2026-98864","ts":1792844774567,"field":"severity","old":"none","new":"medium"}]}