{"id":"CVE-2026-89488","title":"kernel: openvswitch: Fix CT limit teardown use-after-free (CVE-2026-89488)","summary":"A flaw was found in the Linux kernel's Open vSwitch (OVS) component. An unprivileged user, operating from a user and network namespace, can trigger a use-after-free vulnerability during network namespace teardown. This occurs because packe…","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-825","vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","affected":["enterprise_linux 10","enterprise_linux 8","enterprise_linux 9","openshift_container_platform 4","enterprise_linux 6"],"published":"2026-09-11","updated":"2026-09-18","sourceUpdated":"2026-09-18T10:47:46+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89488.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89488.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89488"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532407"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89488"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89488"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89488.mbox"},{"url":"https://git.kernel.org/stable/c/239f26589a6926db28c436e14f28517581ef1385"},{"url":"https://git.kernel.org/stable/c/3b9369881b403f4cdbb11fa998554382bdcc3d8c"},{"url":"https://git.kernel.org/stable/c/3b41d907400cc1dd1da9555b81dca422b1f44433"},{"url":"https://git.kernel.org/stable/c/680f20d5937fa4d1367c59fe83091b78041015f5"},{"url":"https://git.kernel.org/stable/c/bf4aaa7ea2579e24ed7de2e20578a875bebca011"},{"url":"https://git.kernel.org/stable/c/e15407c3a8a005324f633cd46cd8fb58042c1157"},{"url":"https://git.kernel.org/stable/c/6a6d36fadb8537d9b79e72c9fa51885ec0c33e10"},{"url":"https://git.kernel.org/stable/c/403f96c32c9e24600093d7d0c61c17daeedca957"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.00125,"epssPercentile":0.02579,"scores":{"vendor":7,"cna":7.8},"ingestedAt":"2026-09-14T15:23:07.452Z","slug":"CVE-2026-89488","body":"## Overview\n\nA flaw was found in the Linux kernel's Open vSwitch (OVS) component. An unprivileged user, operating from a user and network namespace, can trigger a use-after-free vulnerability during network namespace teardown. This occurs because packet processing attempts to use connection tracking (CT) limit state after it has been freed, leading to a slab-use-after-free condition. This vulnerability could potentially lead to a denial of service.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4, Red Hat Enterprise Linux 6 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, 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-2026-89488.json)\n\n**kernel: openvswitch: Fix CT limit teardown use-after-free** — rated Important 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 8\n- Red Hat Enterprise Linux 9\n- Red Hat OpenShift Container Platform 4\n- Red Hat Enterprise Linux 6\n\nNo fix planned:\n\n- Red Hat Enterprise Linux 10\n- Red Hat Enterprise Linux 8\n- Red Hat Enterprise Linux 9\n- Red Hat OpenShift Container Platform 4\n\nNot affected:\n\n- Red Hat Enterprise Linux 7\n\n## Remediation\n\nAffected","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":38.5,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":206953,"id":"CVE-2026-89488","ts":1789749716783,"field":"cvss","old":"7.8","new":"7"},{"seq":198016,"id":"CVE-2026-89488","ts":1789384321396,"field":"cvss","old":"4.7","new":"7.8"},{"seq":198015,"id":"CVE-2026-89488","ts":1789384321396,"field":"severity","old":"medium","new":"high"},{"seq":183520,"id":"CVE-2026-89488","ts":1789356675703,"field":"cvss","old":"7.8","new":"4.7"},{"seq":183519,"id":"CVE-2026-89488","ts":1789356675703,"field":"severity","old":"high","new":"medium"},{"seq":153274,"id":"CVE-2026-89488","ts":1789285349839,"field":"cvss","old":null,"new":"7.8"},{"seq":153273,"id":"CVE-2026-89488","ts":1789285349839,"field":"severity","old":"none","new":"high"},{"seq":147237,"id":"CVE-2026-89488","ts":1789270203450,"field":"cvss","old":null,"new":"4.7"},{"seq":147236,"id":"CVE-2026-89488","ts":1789270203450,"field":"severity","old":"none","new":"medium"},{"seq":108990,"id":"CVE-2026-89488","ts":1789183729862,"field":"cvss","old":null,"new":"4.7"},{"seq":108989,"id":"CVE-2026-89488","ts":1789183729862,"field":"severity","old":"none","new":"medium"}]}