{"id":"CVE-2026-98490","title":"kernel: net: openvswitch: conntrack: fix helper UAF due to extensions realloc (CVE-2026-98490)","summary":"A flaw was found in the Linux kernel's Open vSwitch subsystem. When connection tracking helpers process unconfirmed connections, subsequent memory reallocations for extensions can leave a dangling pointer in the connection expectations lis…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cvssSource":"vendor","cwe":"CWE-825","vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","affected":["enterprise_linux 10","enterprise_linux 7","enterprise_linux 8","enterprise_linux 9","openshift_container_platform 4"],"published":"2026-10-18","updated":"2026-10-24","sourceUpdated":"2026-10-24T14:22:47+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98490.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98490.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-98490"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2554862"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98490"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98490"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98490.mbox"},{"url":"https://git.kernel.org/stable/c/18866dc1f525f9ee4de7709529d1ae1af8d8e8be"},{"url":"https://git.kernel.org/stable/c/afcf362625190c5260530b1d6c7daa98831f6b83"},{"url":"https://git.kernel.org/stable/c/5f23080a625dd7855ab91485c8d691a54a1979f0"},{"url":"https://git.kernel.org/stable/c/e02a83bb0b7a203f6a22f55ad5f426765560f811"},{"url":"https://git.kernel.org/stable/c/1a4151e6be57b098b7a5ebfbde58585e83200cdc"}],"tags":["csaf","vex","red-hat","cve.org","score-dispute"],"epss":0.00618,"epssPercentile":0.49392,"scores":{"vendor":7.5,"cna":9.8},"ingestedAt":"2026-10-18T15:45:12.294Z","slug":"CVE-2026-98490","body":"## Overview\n\nA flaw was found in the Linux kernel's Open vSwitch subsystem. When connection tracking helpers process unconfirmed connections, subsequent memory reallocations for extensions can leave a dangling pointer in the connection expectations list. An attacker can exploit this issue by sending specially crafted network packets to trigger a use-after-free condition, leading to a Denial of Service (DoS) through a kernel crash or potentially arbitrary code execution.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, … · updated 2026-10-24 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98490.json)\n\n**kernel: net: openvswitch: conntrack: fix helper UAF due to extensions realloc** — rated Important by Red Hat. Released 2026-10-18, updated 2026-10-24.\n\nAffected:\n\n- Red Hat Enterprise Linux 10\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\nNo fix planned:\n\n- Red Hat Enterprise Linux 10\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\nNot affected:\n\n- Red Hat Enterprise Linux 6\n\n## Remediation\n\nAffected\n\nWorkarounds / mitigations:\n\n- --- CME Mitigation Guidance (2026-10-20) ---\nDisclaimer: The following mitigation solutions are provided as a courtesy, pending the application of an official patch. This content was generated utilizing AI tools in conjunction with data from https://cmetaxonomy.org. Customers are advised to independently evaluate and test these temporary mitigations within their own infrastructure.\n\nThe highest-value action is to defer conntrack helper invocation in Open vSwitch until after all connection track…","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":229558,"id":"CVE-2026-98490","ts":1793019846238,"field":"cvss","old":"9.8","new":"7.5"},{"seq":229557,"id":"CVE-2026-98490","ts":1793019846238,"field":"severity","old":"critical","new":"high"},{"seq":228948,"id":"CVE-2026-98490","ts":1792854118291,"field":"cvss","old":null,"new":"9.8"},{"seq":228947,"id":"CVE-2026-98490","ts":1792854118291,"field":"severity","old":"none","new":"critical"}]}