{"id":"CVE-2026-89570","title":"kernel: cxl/mce: Make the MCE notifier per-region (CVE-2026-89570)","summary":"A flaw was found in the Linux kernel's Compute Express Link (CXL) subsystem. Lifetime issues with the CXL Machine Check Exception (MCE) notifier can lead to NULL dereferences and use-after-free vulnerabilities in the MCE handler. This coul…","severity":"high","cvss":7,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","cvssSource":"vendor","cwe":"CWE-476","vendor":"Red Hat","product":"Red Hat Enterprise Linux 10","affected":["enterprise_linux 10"],"published":"2026-09-11","updated":"2026-09-15","sourceUpdated":"2026-09-15T06:52:21+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89570.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89570.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89570"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532510"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89570"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89570"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89570.mbox"},{"url":"https://git.kernel.org/stable/c/491d8c9ac98d55073bda778f88a5248d4cce3fa0"},{"url":"https://git.kernel.org/stable/c/5563db13c9528a56c7161260ec75ec8690dc5608"},{"url":"https://git.kernel.org/stable/c/775d0f4558f4cec0ee0c8966595d1add1791f36e"}],"tags":["csaf","vex","red-hat","cve.org","score-dispute"],"epss":0.00124,"epssPercentile":0.02432,"scores":{"vendor":4.1,"cna":7.8},"ingestedAt":"2026-09-14T15:23:07.474Z","slug":"CVE-2026-89570","body":"## Overview\n\nA flaw was found in the Linux kernel's Compute Express Link (CXL) subsystem. Lifetime issues with the CXL Machine Check Exception (MCE) notifier can lead to NULL dereferences and use-after-free vulnerabilities in the MCE handler. This could allow an attacker to cause system instability or a denial of service.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10 · no fix planned: Red Hat Enterprise Linux 10 · updated 2026-09-15 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89570.json)\n\n**kernel: cxl/mce: Make the MCE notifier per-region** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-15.\n\nAffected:\n\n- Red Hat Enterprise Linux 10\n\nNo fix planned:\n\n- Red Hat Enterprise Linux 10\n\nNot affected:\n\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\nAffected","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":38.5,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":203939,"id":"CVE-2026-89570","ts":1789490229326,"field":"cvss","old":"4.1","new":"7"},{"seq":203938,"id":"CVE-2026-89570","ts":1789490229326,"field":"severity","old":"medium","new":"high"},{"seq":202879,"id":"CVE-2026-89570","ts":1789403732782,"field":"cvss","old":"7.8","new":"4.1"},{"seq":202878,"id":"CVE-2026-89570","ts":1789403732782,"field":"severity","old":"high","new":"medium"},{"seq":197912,"id":"CVE-2026-89570","ts":1789384320917,"field":"cvss","old":"4.1","new":"7.8"},{"seq":197911,"id":"CVE-2026-89570","ts":1789384320917,"field":"severity","old":"medium","new":"high"},{"seq":183469,"id":"CVE-2026-89570","ts":1789356675493,"field":"cvss","old":"7.8","new":"4.1"},{"seq":183468,"id":"CVE-2026-89570","ts":1789356675493,"field":"severity","old":"high","new":"medium"},{"seq":153384,"id":"CVE-2026-89570","ts":1789285350298,"field":"cvss","old":null,"new":"7.8"},{"seq":153383,"id":"CVE-2026-89570","ts":1789285350298,"field":"severity","old":"none","new":"high"},{"seq":147097,"id":"CVE-2026-89570","ts":1789270195157,"field":"cvss","old":null,"new":"4.1"},{"seq":147096,"id":"CVE-2026-89570","ts":1789270195157,"field":"severity","old":"none","new":"medium"},{"seq":108852,"id":"CVE-2026-89570","ts":1789183729257,"field":"cvss","old":null,"new":"4.1"},{"seq":108851,"id":"CVE-2026-89570","ts":1789183729257,"field":"severity","old":"none","new":"medium"}]}