{"id":"CVE-2026-89443","title":"platform/x86: ISST: Validate level in perf mask ioctls","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nplatform/x86: ISST: Validate level in perf mask ioctls\n\nisst_if_get_perf_level_mask() and isst_if_get_base_freq_mask() use the\nuser-provided level as an index into perf…","severity":"high","cvss":7.1,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","cvssSource":"cna","cwe":["CWE-125"],"vendor":"Linux","product":"Linux","affected":["Linux >= ea009e4769fa3bd05d4c111c3b6865eb3a9be829 < beb22ebf76c0415f22d2d0c3f1ff0627e7ae4a68","Linux >= ea009e4769fa3bd05d4c111c3b6865eb3a9be829 < 1a8bab5ceee1a42a78de12d3d69f67516a20588e","Linux >= ea009e4769fa3bd05d4c111c3b6865eb3a9be829 < 1889a9156553f0692acd57caf15e877baace1a01","Linux >= ea009e4769fa3bd05d4c111c3b6865eb3a9be829 < d19385624bdfb577db9c94bb8879992fd5e17bcd","Linux >= ea009e4769fa3bd05d4c111c3b6865eb3a9be829 < 80e0d353c86a9a168ad6d213f494796294381538","Linux 6.4"],"published":"2026-09-11","updated":"2026-10-19","sourceUpdated":"2026-10-19T08:46:52.766Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-89443","references":[{"url":"https://git.kernel.org/stable/c/beb22ebf76c0415f22d2d0c3f1ff0627e7ae4a68"},{"url":"https://git.kernel.org/stable/c/1a8bab5ceee1a42a78de12d3d69f67516a20588e"},{"url":"https://git.kernel.org/stable/c/1889a9156553f0692acd57caf15e877baace1a01"},{"url":"https://git.kernel.org/stable/c/d19385624bdfb577db9c94bb8879992fd5e17bcd"},{"url":"https://git.kernel.org/stable/c/80e0d353c86a9a168ad6d213f494796294381538"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89443.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89443"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532417"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89443"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89443"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89443.mbox"}],"tags":["cve.org","csaf","vex","red-hat"],"epss":0.00163,"epssPercentile":0.05487,"scores":{"cna":7.1,"vendor":5.5},"ingestedAt":"2026-09-14T15:23:07.453Z","slug":"CVE-2026-89443","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nplatform/x86: ISST: Validate level in perf mask ioctls\n\nisst_if_get_perf_level_mask() and isst_if_get_base_freq_mask() use the\nuser-provided level as an index into perf_levels[] via\n_read_pp_level_info() and _read_bf_level_info(), but neither helper\nvalidates it first.\n\nThe adjacent level-info helpers reject levels above max_level before\nreading the same per-level register block. Add the same bounds checks to\nthe mask helpers, and reject disabled SST-PP levels in\nisst_if_get_perf_level_mask() to match isst_if_get_perf_level_info().\n\nThis prevents out-of-bounds reads from the per-level offset table on\ninvalid ioctl input.\n\n## Affected\n\n- `Linux >= ea009e4769fa3bd05d4c111c3b6865eb3a9be829 < beb22ebf76c0415f22d2d0c3f1ff0627e7ae4a68`\n- `Linux >= ea009e4769fa3bd05d4c111c3b6865eb3a9be829 < 1a8bab5ceee1a42a78de12d3d69f67516a20588e`\n- `Linux >= ea009e4769fa3bd05d4c111c3b6865eb3a9be829 < 1889a9156553f0692acd57caf15e877baace1a01`\n- `Linux >= ea009e4769fa3bd05d4c111c3b6865eb3a9be829 < d19385624bdfb577db9c94bb8879992fd5e17bcd`\n- `Linux >= ea009e4769fa3bd05d4c111c3b6865eb3a9be829 < 80e0d353c86a9a168ad6d213f494796294381538`\n- `Linux 6.4`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\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 2026-10-17 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89443.json)","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":39.1,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":224761,"id":"CVE-2026-89443","ts":1792401529026,"field":"cvss","old":"5.5","new":"7.1"},{"seq":224760,"id":"CVE-2026-89443","ts":1792401529026,"field":"severity","old":"medium","new":"high"},{"seq":204111,"id":"CVE-2026-89443","ts":1789490231614,"field":"cvss","old":"7.1","new":"5.5"},{"seq":204110,"id":"CVE-2026-89443","ts":1789490231614,"field":"severity","old":"high","new":"medium"},{"seq":198055,"id":"CVE-2026-89443","ts":1789384321574,"field":"cvss","old":"4.4","new":"7.1"},{"seq":198054,"id":"CVE-2026-89443","ts":1789384321574,"field":"severity","old":"medium","new":"high"},{"seq":183546,"id":"CVE-2026-89443","ts":1789356675830,"field":"cvss","old":"7.1","new":"4.4"},{"seq":183545,"id":"CVE-2026-89443","ts":1789356675830,"field":"severity","old":"high","new":"medium"},{"seq":153226,"id":"CVE-2026-89443","ts":1789285349628,"field":"cvss","old":null,"new":"7.1"},{"seq":153225,"id":"CVE-2026-89443","ts":1789285349628,"field":"severity","old":"none","new":"high"},{"seq":147241,"id":"CVE-2026-89443","ts":1789270203745,"field":"cvss","old":null,"new":"4.4"},{"seq":147240,"id":"CVE-2026-89443","ts":1789270203745,"field":"severity","old":"none","new":"medium"},{"seq":108998,"id":"CVE-2026-89443","ts":1789183729893,"field":"cvss","old":null,"new":"4.4"},{"seq":108997,"id":"CVE-2026-89443","ts":1789183729893,"field":"severity","old":"none","new":"medium"}]}