{"id":"CVE-2026-89758","title":"kernel: mm/mempolicy: skip non-present PMDs when queueing folios (CVE-2026-89758)","summary":"A flaw was found in the Linux kernel's memory management subsystem. When an HMM-based Graphics Processing Unit (GPU) driver migrates a Transparent Huge Page (THP) to device memory, it can leave a device-private Page Middle Directory (PMD) …","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-824","vendor":"Red Hat","product":"Red Hat Enterprise Linux 6","affected":["enterprise_linux 6"],"published":"2026-09-11","updated":"2026-09-21","sourceUpdated":"2026-09-21T17:54:36+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89758.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89758.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89758"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532153"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89758"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89758"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89758.mbox"},{"url":"https://git.kernel.org/stable/c/2858b4027f491e6fdb8ee2d8923798b619bf2791"},{"url":"https://git.kernel.org/stable/c/3d927093b2add7ced588a926c3dc5d7a83f18596"}],"tags":["csaf","vex","red-hat","cve.org","score-dispute"],"epss":0.00143,"epssPercentile":0.04008,"scores":{"vendor":4.7,"cna":7.8},"ingestedAt":"2026-09-14T15:23:07.472Z","slug":"CVE-2026-89758","body":"## Overview\n\nA flaw was found in the Linux kernel's memory management subsystem. When an HMM-based Graphics Processing Unit (GPU) driver migrates a Transparent Huge Page (THP) to device memory, it can leave a device-private Page Middle Directory (PMD) entry. If a user-space application then attempts to manage this memory range, the kernel may incorrectly process the non-present PMD, leading to a system crash. This vulnerability could allow a local attacker to cause a Denial of Service (DoS).\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-2026-89758.json)\n\n**kernel: mm/mempolicy: skip non-present PMDs when queueing folios** — 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":208939,"id":"CVE-2026-89758","ts":1790062296081,"field":"cvss","old":"4.7","new":"7"},{"seq":208938,"id":"CVE-2026-89758","ts":1790062296081,"field":"severity","old":"medium","new":"high"},{"seq":202960,"id":"CVE-2026-89758","ts":1789403733122,"field":"cvss","old":"7.8","new":"4.7"},{"seq":202959,"id":"CVE-2026-89758","ts":1789403733122,"field":"severity","old":"high","new":"medium"},{"seq":197668,"id":"CVE-2026-89758","ts":1789384318320,"field":"cvss","old":"4.7","new":"7.8"},{"seq":197667,"id":"CVE-2026-89758","ts":1789384318320,"field":"severity","old":"medium","new":"high"},{"seq":183649,"id":"CVE-2026-89758","ts":1789356676255,"field":"cvss","old":"7.8","new":"4.7"},{"seq":183648,"id":"CVE-2026-89758","ts":1789356676255,"field":"severity","old":"high","new":"medium"},{"seq":153644,"id":"CVE-2026-89758","ts":1789285351699,"field":"cvss","old":null,"new":"7.8"},{"seq":153643,"id":"CVE-2026-89758","ts":1789285351699,"field":"severity","old":"none","new":"high"},{"seq":147666,"id":"CVE-2026-89758","ts":1789270211803,"field":"cvss","old":null,"new":"4.7"},{"seq":147665,"id":"CVE-2026-89758","ts":1789270211803,"field":"severity","old":"none","new":"medium"},{"seq":109420,"id":"CVE-2026-89758","ts":1789183731844,"field":"cvss","old":null,"new":"4.7"},{"seq":109419,"id":"CVE-2026-89758","ts":1789183731844,"field":"severity","old":"none","new":"medium"}]}