{"id":"CVE-2026-89581","title":"kernel: bpf, x86: Fix per-CPU address resolution into an extended register (CVE-2026-89581)","summary":"A flaw was found in the Linux kernel's handling of Berkeley Packet Filter (BPF) programs on x86 architecture. An issue with how per-CPU addresses are resolved into extended registers can lead to incorrect memory access. A local attacker co…","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 9","affected":["enterprise_linux 10","enterprise_linux 9","openshift_container_platform 4"],"published":"2026-09-11","updated":"2026-09-18","sourceUpdated":"2026-09-18T22:12:21+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89581.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89581.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89581"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532189"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89581"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89581"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89581.mbox"},{"url":"https://git.kernel.org/stable/c/5bbbce02e500d47d8e259a45be5a7be9741d0533"},{"url":"https://git.kernel.org/stable/c/638bc3aada8ecdece184d5c15b100d489c9cccd7"},{"url":"https://git.kernel.org/stable/c/6886642414f59f928728802dc2c972a9859e6310"},{"url":"https://git.kernel.org/stable/c/6a19b18d458881bf3269a357cc6dc6db5eef4369"}],"tags":["csaf","vex","red-hat","cve.org","score-dispute"],"epss":0.00128,"epssPercentile":0.02852,"scores":{"vendor":5.5,"cna":7.8},"ingestedAt":"2026-09-14T15:23:07.474Z","slug":"CVE-2026-89581","body":"## Overview\n\nA flaw was found in the Linux kernel's handling of Berkeley Packet Filter (BPF) programs on x86 architecture. An issue with how per-CPU addresses are resolved into extended registers can lead to incorrect memory access. A local attacker could exploit this by running a specially crafted BPF program. This could cause a kernel panic, resulting in a denial of service (DoS) to the system.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-09-18 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89581.json)\n\n**kernel: bpf, x86: Fix per-CPU address resolution into an extended register** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-18.\n\nAffected:\n\n- Red Hat Enterprise Linux 10\n- Red Hat Enterprise Linux 9\n- Red Hat OpenShift Container Platform 4\n\nNo fix planned:\n\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 6\n- Red Hat Enterprise Linux 7\n- Red Hat Enterprise Linux 8\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":208091,"id":"CVE-2026-89581","ts":1789922707550,"field":"cvss","old":"5.5","new":"7"},{"seq":208090,"id":"CVE-2026-89581","ts":1789922707550,"field":"severity","old":"medium","new":"high"},{"seq":202869,"id":"CVE-2026-89581","ts":1789403732741,"field":"cvss","old":"7.8","new":"5.5"},{"seq":202868,"id":"CVE-2026-89581","ts":1789403732741,"field":"severity","old":"high","new":"medium"},{"seq":197900,"id":"CVE-2026-89581","ts":1789384320870,"field":"cvss","old":"5.5","new":"7.8"},{"seq":197899,"id":"CVE-2026-89581","ts":1789384320870,"field":"severity","old":"medium","new":"high"},{"seq":183447,"id":"CVE-2026-89581","ts":1789356675405,"field":"cvss","old":"7.8","new":"5.5"},{"seq":183446,"id":"CVE-2026-89581","ts":1789356675405,"field":"severity","old":"high","new":"medium"},{"seq":153396,"id":"CVE-2026-89581","ts":1789285350346,"field":"cvss","old":null,"new":"7.8"},{"seq":153395,"id":"CVE-2026-89581","ts":1789285350346,"field":"severity","old":"none","new":"high"},{"seq":147612,"id":"CVE-2026-89581","ts":1789270211594,"field":"cvss","old":null,"new":"5.5"},{"seq":147611,"id":"CVE-2026-89581","ts":1789270211594,"field":"severity","old":"none","new":"medium"},{"seq":109362,"id":"CVE-2026-89581","ts":1789183731614,"field":"cvss","old":null,"new":"5.5"},{"seq":109361,"id":"CVE-2026-89581","ts":1789183731614,"field":"severity","old":"none","new":"medium"}]}