{"id":"CVE-2026-98476","title":"kernel: s390/cio: Fix NULL pointer dereference in ccw_device_get_util_str() (CVE-2026-98476)","summary":"A flaw was found in the Linux kernel's s390 channel I/O (CIO) subsystem. When querying device utility strings, the kernel fails to verify that an associated channel path remains valid after its removal from the registry. A local user could…","severity":"medium","cvss":4.7,"cvssVector":"CVSS:3.1/AV:L/AC:H/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":"2026-10-18","updated":"2026-10-20","sourceUpdated":"2026-10-20T11:13:57+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98476.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98476.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-98476"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2554875"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98476"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98476"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98476.mbox"},{"url":"https://git.kernel.org/stable/c/9d8b21820caed9128945fffcedf03e2a4c21eee2"},{"url":"https://git.kernel.org/stable/c/5fc54e04dad90b15d0430118b3f288a1d64e66c9"},{"url":"https://git.kernel.org/stable/c/27e396a89f76f742abdbe9f8c4a58a6e806fdf59"},{"url":"https://git.kernel.org/stable/c/dbf30e661ceb9a52c94c85719716391dcc29142a"},{"url":"https://git.kernel.org/stable/c/5e006ac90a4d331db1dd712b91fec849b45ffc01"},{"url":"https://git.kernel.org/stable/c/c3bbcb32deecc06ebb1762398399b566d5ff2fc9"},{"url":"https://git.kernel.org/stable/c/44b16b02608058fc72198ac0205969f0f43065df"},{"url":"https://git.kernel.org/stable/c/5b76268dac968612f7283d59b539036de955b7d9"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.00177,"epssPercentile":0.07147,"ingestedAt":"2026-10-18T15:45:12.298Z","slug":"CVE-2026-98476","body":"## Overview\n\nA flaw was found in the Linux kernel's s390 channel I/O (CIO) subsystem. When querying device utility strings, the kernel fails to verify that an associated channel path remains valid after its removal from the registry. A local user could exploit this condition during hardware reconfiguration, resulting in a NULL pointer dereference that causes a system crash and Denial of Service (DoS).\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 2026-10-20 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98476.json)\n\n**kernel: s390/cio: Fix NULL pointer dereference in ccw_device_get_util_str()** — rated Moderate by Red Hat. Released 2026-10-18, updated 2026-10-20.\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":26,"depthScoreParts":{"impact":25.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":225656,"id":"CVE-2026-98476","ts":1792498338119,"field":"cvss","old":null,"new":"4.7"},{"seq":225655,"id":"CVE-2026-98476","ts":1792498338119,"field":"severity","old":"none","new":"medium"}]}