{"id":"CVE-2026-98866","title":"kernel: sched/cache: Introduce task_struct->sched_cache_grp to fix UAF (CVE-2026-98866)","summary":"A flaw was found in the Linux kernel. A use-after-free vulnerability, where memory is accessed after being released, occurs in the process scheduler cache component during task memory switches. A local user could exploit this flaw to cause…","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-825","vendor":"Red Hat","product":"Red Hat Enterprise Linux 6","affected":["enterprise_linux 6"],"published":"2026-10-18","updated":"2026-10-24","sourceUpdated":"2026-10-24T07:31:43+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98866.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98866.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-98866"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2555204"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98866"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98866"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98866.mbox"},{"url":"https://git.kernel.org/stable/c/9436130e6da72af63289a4acb3aa0c1df07a3928"},{"url":"https://git.kernel.org/stable/c/b636fef85bda7d1bab9c0a45067ab1508d79d946"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.00145,"epssPercentile":0.03753,"ingestedAt":"2026-10-18T16:47:32.458Z","slug":"CVE-2026-98866","body":"## Overview\n\nA flaw was found in the Linux kernel. A use-after-free vulnerability, where memory is accessed after being released, occurs in the process scheduler cache component during task memory switches. A local user could exploit this flaw to cause a Denial of Service (DoS) through a system crash.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 6 · no fix planned: Red Hat Enterprise Linux 6 · updated 2026-10-24 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98866.json)\n\n**kernel: sched/cache: Introduce task_struct->sched_cache_grp to fix UAF** — rated Moderate by Red Hat. Released 2026-10-18, updated 2026-10-24.\n\nAffected:\n\n- Red Hat Enterprise Linux 6\n\nNo fix planned:\n\n- Red Hat Enterprise Linux 6\n\nNot affected:\n\n- Red Hat Enterprise Linux 10\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\nOut of support scope","depth":"sunlit","depthScore":26,"depthScoreParts":{"impact":25.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":228518,"id":"CVE-2026-98866","ts":1792844772400,"field":"cvss","old":null,"new":"4.7"},{"seq":228517,"id":"CVE-2026-98866","ts":1792844772400,"field":"severity","old":"none","new":"medium"}]}