{"id":"CVE-2026-89500","title":"kernel: ring-buffer: Make cpu_buffer::free_page a buffer_data_read_page (CVE-2026-89500)","summary":"A flaw was found in the Linux kernel's ring-buffer component. When a cached reader page is discarded after a concurrent ring buffer resize, the system may use an incorrect buffer size for memory deallocation. This mismatch can lead to a ke…","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-763","vendor":"Red Hat","product":"Red Hat Enterprise Linux 10","affected":["enterprise_linux 10"],"published":"2026-09-11","updated":"2026-09-15","sourceUpdated":"2026-09-15T08:13:16+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89500.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89500.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89500"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532513"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89500"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89500"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89500.mbox"},{"url":"https://git.kernel.org/stable/c/7a1fb95de5404134f8758c1295ce88986bdf117c"},{"url":"https://git.kernel.org/stable/c/a1dabe68fb53730bc0be60c5dbfd3f4c560084e7"},{"url":"https://git.kernel.org/stable/c/d787d509bdf6c88c85e095247daf7456cb7fb772"}],"tags":["csaf","vex","red-hat","cve.org","score-dispute"],"epss":0.00173,"epssPercentile":0.05927,"scores":{"vendor":4.1,"cna":7.8},"ingestedAt":"2026-09-14T15:23:07.475Z","slug":"CVE-2026-89500","body":"## Overview\n\nA flaw was found in the Linux kernel's ring-buffer component. When a cached reader page is discarded after a concurrent ring buffer resize, the system may use an incorrect buffer size for memory deallocation. This mismatch can lead to a kernel crash, resulting in a Denial of Service (DoS), or it could cause memory leaks, potentially leading to information disclosure.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10 · no fix planned: Red Hat Enterprise Linux 10 · updated 2026-09-15 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89500.json)\n\n**kernel: ring-buffer: Make cpu_buffer::free_page a buffer_data_read_page** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-15.\n\nAffected:\n\n- Red Hat Enterprise Linux 10\n\nNo fix planned:\n\n- Red Hat Enterprise Linux 10\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 Enterprise Linux 9\n- Red Hat OpenShift Container Platform 4\n\n## Remediation\n\nAffected","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":38.5,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":203931,"id":"CVE-2026-89500","ts":1789490227190,"field":"cvss","old":"4.1","new":"7"},{"seq":203930,"id":"CVE-2026-89500","ts":1789490227190,"field":"severity","old":"medium","new":"high"},{"seq":202899,"id":"CVE-2026-89500","ts":1789403732862,"field":"cvss","old":"7.8","new":"4.1"},{"seq":202898,"id":"CVE-2026-89500","ts":1789403732862,"field":"severity","old":"high","new":"medium"},{"seq":197998,"id":"CVE-2026-89500","ts":1789384321311,"field":"cvss","old":"4.1","new":"7.8"},{"seq":197997,"id":"CVE-2026-89500","ts":1789384321311,"field":"severity","old":"medium","new":"high"},{"seq":183508,"id":"CVE-2026-89500","ts":1789356675656,"field":"cvss","old":"7.8","new":"4.1"},{"seq":183507,"id":"CVE-2026-89500","ts":1789356675656,"field":"severity","old":"high","new":"medium"},{"seq":153290,"id":"CVE-2026-89500","ts":1789285349905,"field":"cvss","old":null,"new":"7.8"},{"seq":153289,"id":"CVE-2026-89500","ts":1789285349905,"field":"severity","old":"none","new":"high"},{"seq":147071,"id":"CVE-2026-89500","ts":1789270195046,"field":"cvss","old":null,"new":"4.1"},{"seq":147070,"id":"CVE-2026-89500","ts":1789270195046,"field":"severity","old":"none","new":"medium"}]}