{"id":"CVE-2026-89460","title":"kernel: s390/cpum_cf: Handle CPU hotplug via prepare/dead callbacks (CVE-2026-89460)","summary":"A flaw was found in the Linux kernel. A local user can trigger a kernel panic by running the `perf stat` command while CPUs are being hotplugged. This occurs because the system fails to properly allocate CPU event structures for newly onli…","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-476","vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","affected":["enterprise_linux 10","enterprise_linux 6","enterprise_linux 9","openshift_container_platform 4"],"published":"2026-09-11","updated":"2026-09-16","sourceUpdated":"2026-09-16T07:34:00+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89460.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89460.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89460"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532364"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89460"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89460"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89460.mbox"},{"url":"https://git.kernel.org/stable/c/337bd95507a16063687cfc286ea90de5cca48c37"},{"url":"https://git.kernel.org/stable/c/71d46de9153e067c63a15f3b00e6364e1c0230f8"},{"url":"https://git.kernel.org/stable/c/777d040c2f91d8d929b4a32333dfe4102b27caea"},{"url":"https://git.kernel.org/stable/c/dcce7a06ea690d5cf46a705a9b74cf0398ac091f"},{"url":"https://git.kernel.org/stable/c/991be92489bc7b1b6e7903debb96bd58c892dee4"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.00168,"epssPercentile":0.06443,"ingestedAt":"2026-09-14T15:23:07.453Z","slug":"CVE-2026-89460","body":"## Overview\n\nA flaw was found in the Linux kernel. A local user can trigger a kernel panic by running the `perf stat` command while CPUs are being hotplugged. This occurs because the system fails to properly allocate CPU event structures for newly online CPUs, leading to a null pointer dereference. Successful exploitation results in a Denial of Service (DoS) due to a system crash.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-09-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89460.json)\n\n**kernel: s390/cpum_cf: Handle CPU hotplug via prepare/dead callbacks** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-16.\n\nAffected:\n\n- Red Hat Enterprise Linux 10\n- Red Hat Enterprise Linux 6\n- Red Hat Enterprise Linux 9\n- Red Hat OpenShift Container Platform 4\n\nNo fix planned:\n\n- Red Hat Enterprise Linux 6\n- Red Hat Enterprise Linux 10\n- Red Hat Enterprise Linux 9\n- Red Hat OpenShift Container Platform 4\n\nNot affected:\n\n- Red Hat Enterprise Linux 7\n- Red Hat Enterprise Linux 8\n- Red Hat OpenShift Container Platform 4\n\n## Remediation\n\nOut of support scope","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":205482,"id":"CVE-2026-89460","ts":1789576721755,"field":"cvss","old":"4.4","new":"5.5"},{"seq":204005,"id":"CVE-2026-89460","ts":1789490231012,"field":"cvss","old":null,"new":"4.4"},{"seq":204004,"id":"CVE-2026-89460","ts":1789490231012,"field":"severity","old":"none","new":"medium"},{"seq":147335,"id":"CVE-2026-89460","ts":1789270210502,"field":"cvss","old":null,"new":"4.4"},{"seq":147334,"id":"CVE-2026-89460","ts":1789270210502,"field":"severity","old":"none","new":"medium"},{"seq":109090,"id":"CVE-2026-89460","ts":1789183730267,"field":"cvss","old":null,"new":"4.4"},{"seq":109089,"id":"CVE-2026-89460","ts":1789183730267,"field":"severity","old":"none","new":"medium"}]}