{"id":"CVE-2026-98546","title":"kernel: arm64/boot: Disable trapping of PMZR_EL0 writes to EL2 (CVE-2026-98546)","summary":"A flaw was found in the Linux kernel's ARM64 architecture support. When user-space access to performance monitoring counters is enabled, write traps for a write-only performance register are improperly configured during hypervisor initiali…","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-617","vendor":"Red Hat","product":"Linux","affected":["Linux >= 686d8f7b592f3466f44aea653c8147611b351c83 < bb8c90c86441c090e9036f019cf1b4d7894a2c40","Linux >= 858c7bfcb35e1100b58bb63c9f562d86e09418d9 < 071f51188a5d8ec10535541255587976d12fc7d8","Linux >= 858c7bfcb35e1100b58bb63c9f562d86e09418d9 < ce71865bf43f88bed9d9218e9218e537150be506","Linux >= 858c7bfcb35e1100b58bb63c9f562d86e09418d9 < 2bc6b218717b9d08f466f88209251d54bc09b207","Linux 882f78400322c0aec4b641a7168adad9a66bc0c2","Linux >= 6.12.25 < 6.12.112","Linux >= 6.14.4 < 6.15","Linux 6.15"],"published":"2026-10-18","updated":"2026-10-20","sourceUpdated":"2026-10-20T00:14:26+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98546.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98546.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-98546"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2554987"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98546"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98546"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98546.mbox"},{"url":"https://git.kernel.org/stable/c/bb8c90c86441c090e9036f019cf1b4d7894a2c40"},{"url":"https://git.kernel.org/stable/c/071f51188a5d8ec10535541255587976d12fc7d8"},{"url":"https://git.kernel.org/stable/c/ce71865bf43f88bed9d9218e9218e537150be506"},{"url":"https://git.kernel.org/stable/c/2bc6b218717b9d08f466f88209251d54bc09b207"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.002,"epssPercentile":0.0978,"ingestedAt":"2026-10-18T15:45:12.266Z","slug":"CVE-2026-98546","body":"## Overview\n\nA flaw was found in the Linux kernel's ARM64 architecture support. When user-space access to performance monitoring counters is enabled, write traps for a write-only performance register are improperly configured during hypervisor initialization. A local user can exploit this vulnerability by issuing a write to this register, triggering an unhandled hypervisor exception that leads to a Denial of Service (DoS) through a host system crash.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · updated 2026-10-20 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98546.json)\n\n**kernel: arm64/boot: Disable trapping of PMZR_EL0 writes to EL2** — rated Moderate by Red Hat. Released 2026-10-18, updated 2026-10-20.\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":225830,"id":"CVE-2026-98546","ts":1792498468864,"field":"cvss","old":null,"new":"4.7"},{"seq":225829,"id":"CVE-2026-98546","ts":1792498468864,"field":"severity","old":"none","new":"medium"}]}