{"id":"CVE-2026-98442","title":"kernel: net/sched: act_ct: fix helper UAF due to extensions realloc (CVE-2026-98442)","summary":"A flaw was found in the Linux kernel's traffic control connection tracking action (act_ct). An attacker capable of sending network traffic handled by the affected system can cause a Denial of Service (DoS) or kernel memory corruption throu…","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 9","openshift_container_platform 4"],"published":"2026-10-18","updated":"2026-10-24","sourceUpdated":"2026-10-24T14:27:31+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98442.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98442.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-98442"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2554848"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98442"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98442"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98442.mbox"},{"url":"https://git.kernel.org/stable/c/31f5fe29a572037ee19c233dfe506849940c484b"},{"url":"https://git.kernel.org/stable/c/1679bbf5fbeac52a310b1a58b2b301bbf388bdbf"},{"url":"https://git.kernel.org/stable/c/812c16a255e7773a544e88b39ae6daed25544d30"},{"url":"https://git.kernel.org/stable/c/8988f4d11f3fba0ab38122178836c683ad516a05"},{"url":"https://git.kernel.org/stable/c/dad19b59da050cb60d3f7023dac2a042a84bf0bd"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.00129,"epssPercentile":0.02524,"scores":{"vendor":7.5,"cna":7.8},"ingestedAt":"2026-10-18T15:45:12.307Z","slug":"CVE-2026-98442","body":"## Overview\n\nA flaw was found in the Linux kernel's traffic control connection tracking action (act_ct). An attacker capable of sending network traffic handled by the affected system can cause a Denial of Service (DoS) or kernel memory corruption through a use-after-free vulnerability. This issue occurs because connection tracking helpers record pointers to extension memory before all extensions are added, leaving invalid references when memory is subsequently reallocated.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Important · 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 2026-10-24 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98442.json)\n\n**kernel: net/sched: act_ct: 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 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\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 ensure conntrack helper functions run only after all connection tracking extension…","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":229513,"id":"CVE-2026-98442","ts":1793019829788,"field":"cvss","old":"7.8","new":"7.5"},{"seq":228972,"id":"CVE-2026-98442","ts":1792854125614,"field":"cvss","old":null,"new":"7.8"},{"seq":228971,"id":"CVE-2026-98442","ts":1792854125614,"field":"severity","old":"none","new":"high"}]}