{"id":"CVE-2026-89754","title":"kernel: mm/pagewalk: fix stale walk->action escaping walk_pmd_range() (CVE-2026-89754)","summary":"A flaw was found in the Linux kernel's memory management (mm/pagewalk) component. An issue in the `walk_pmd_range()` function, where a stale `walk->action` state is not properly reset, can lead to duplicate walk callbacks. A local attacker…","severity":"high","cvss":7,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","cvssSource":"vendor","cwe":"CWE-787","vendor":"Red Hat","product":"Red Hat Enterprise Linux 6","affected":["enterprise_linux 6"],"published":"2026-09-11","updated":"2026-09-21","sourceUpdated":"2026-09-21T17:39:28+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89754.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89754.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89754"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532276"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89754"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89754"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89754.mbox"},{"url":"https://git.kernel.org/stable/c/895cd4ecbb2e03d7583103c65ee5adaae126ed6d"},{"url":"https://git.kernel.org/stable/c/c05cdc2ab365b98099386e6c166b9865a4f2a9d3"},{"url":"https://git.kernel.org/stable/c/aedf2efd18977e0cef7eb963166e2b1fcc0aa321"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.00118,"epssPercentile":0.01976,"scores":{"vendor":7,"cna":7.8},"ingestedAt":"2026-09-14T15:23:07.472Z","slug":"CVE-2026-89754","body":"## Overview\n\nA flaw was found in the Linux kernel's memory management (mm/pagewalk) component. An issue in the `walk_pmd_range()` function, where a stale `walk->action` state is not properly reset, can lead to duplicate walk callbacks. A local attacker could exploit this to trigger an out-of-bounds write, potentially causing memory corruption and system instability.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 6 · no fix planned: Red Hat Enterprise Linux 6 · updated 2026-09-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89754.json)\n\n**kernel: mm/pagewalk: fix stale walk->action escaping walk_pmd_range()** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-21.\n\nAffected:\n\n- Red Hat Enterprise Linux 6\n\nNo fix planned:\n\n- Red Hat Enterprise Linux 6\n\nNot affected:\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\n## Remediation\n\nOut of support scope","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":38.5,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":208942,"id":"CVE-2026-89754","ts":1790062297122,"field":"cvss","old":"7.8","new":"7"},{"seq":197672,"id":"CVE-2026-89754","ts":1789384318335,"field":"cvss","old":"6.3","new":"7.8"},{"seq":197671,"id":"CVE-2026-89754","ts":1789384318335,"field":"severity","old":"medium","new":"high"},{"seq":183847,"id":"CVE-2026-89754","ts":1789356677654,"field":"cvss","old":"7.8","new":"6.3"},{"seq":183846,"id":"CVE-2026-89754","ts":1789356677654,"field":"severity","old":"high","new":"medium"},{"seq":153640,"id":"CVE-2026-89754","ts":1789285351675,"field":"cvss","old":null,"new":"7.8"},{"seq":153639,"id":"CVE-2026-89754","ts":1789285351675,"field":"severity","old":"none","new":"high"},{"seq":147458,"id":"CVE-2026-89754","ts":1789270210986,"field":"cvss","old":null,"new":"6.3"},{"seq":147457,"id":"CVE-2026-89754","ts":1789270210986,"field":"severity","old":"none","new":"medium"},{"seq":109224,"id":"CVE-2026-89754","ts":1789183730794,"field":"cvss","old":null,"new":"6.3"},{"seq":109223,"id":"CVE-2026-89754","ts":1789183730794,"field":"severity","old":"none","new":"medium"}]}