{"id":"CVE-2026-89439","title":"kernel: platform/x86: ISST: Add a NULL check for sst_inst[] (CVE-2026-89439)","summary":"A flaw was found in the Linux kernel's Intel Speed Select Technology (ISST) driver. A missing NULL check for `isst_common.sst_inst[]` during failed socket loading could allow a local attacker to trigger a NULL pointer dereference. This vul…","severity":"medium","cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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":"2026-09-14","sourceUpdated":"2026-09-14T21:37:38+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89439.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89439.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89439"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532216"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89439"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89439"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89439.mbox"},{"url":"https://git.kernel.org/stable/c/49a95fe1f64f41c2e8959e525aefdb10f23b293e"},{"url":"https://git.kernel.org/stable/c/c280fcd53b938b70c7dee9ce1a66b32bd6e5ebaa"},{"url":"https://git.kernel.org/stable/c/ef7975af15126dd70ace519da7bb33f2848b9064"},{"url":"https://git.kernel.org/stable/c/3de2776e9d7073765c10c2326c2bda5926811ea6"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.002,"epssPercentile":0.10108,"ingestedAt":"2026-09-14T00:35:28.531Z","slug":"CVE-2026-89439","body":"## Overview\n\nA flaw was found in the Linux kernel's Intel Speed Select Technology (ISST) driver. A missing NULL check for `isst_common.sst_inst[]` during failed socket loading could allow a local attacker to trigger a NULL pointer dereference. This vulnerability could lead to a system crash, resulting in a Denial of Service (DoS).\n\n## Vendor advisories\n\n- **Red Hat VEX** · Low · 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 2026-09-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89439.json)\n\n**kernel: platform/x86: ISST: Add a NULL check for sst_inst[]** — rated Low by Red Hat. Released 2026-09-11, updated 2026-09-14.\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\nFix deferred","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":204115,"id":"CVE-2026-89439","ts":1789490231724,"field":"cvss","old":null,"new":"5.5"},{"seq":204114,"id":"CVE-2026-89439","ts":1789490231724,"field":"severity","old":"none","new":"medium"},{"seq":147534,"id":"CVE-2026-89439","ts":1789270211286,"field":"cvss","old":null,"new":"4.4"},{"seq":147533,"id":"CVE-2026-89439","ts":1789270211286,"field":"severity","old":"none","new":"medium"},{"seq":109284,"id":"CVE-2026-89439","ts":1789183731275,"field":"cvss","old":null,"new":"4.4"},{"seq":109283,"id":"CVE-2026-89439","ts":1789183731275,"field":"severity","old":"none","new":"medium"}]}