{"id":"CVE-2026-89767","title":"kernel: ovl: fix double end_creating() on the casefold-mismatch path (CVE-2026-89767)","summary":"A flaw was found in the Linux kernel's overlay file system (overlayfs). An unprivileged local user can trigger a specific error condition during the creation of a new directory. This error causes the system to incorrectly release a lock on…","severity":"medium","cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cvssSource":"vendor","cwe":"CWE-1341","vendor":"Red Hat","product":"Red Hat OpenShift Container Platform 4","affected":["openshift_container_platform 4"],"published":"2026-09-11","updated":"2026-09-15","sourceUpdated":"2026-09-15T10:22:20+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89767.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89767.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89767"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532416"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89767"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89767"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89767.mbox"},{"url":"https://git.kernel.org/stable/c/077ab8985ee278c3d8618182d335b0f0cd919e16"},{"url":"https://git.kernel.org/stable/c/2fa220bc0f84597cb6de665e5b5021c5901ddf00"},{"url":"https://git.kernel.org/stable/c/b1aa8ab78a8e87aee9e306971465408e059f839a"}],"tags":["csaf","vex","red-hat","cve.org","score-dispute"],"epss":0.00151,"epssPercentile":0.04638,"scores":{"vendor":5.5,"cna":7.8},"ingestedAt":"2026-09-14T15:23:07.472Z","slug":"CVE-2026-89767","body":"## Overview\n\nA flaw was found in the Linux kernel's overlay file system (overlayfs). An unprivileged local user can trigger a specific error condition during the creation of a new directory. This error causes the system to incorrectly release a lock on the parent directory and a reference to the new directory entry twice. This double release can lead to subsequent attempts to create directories under the same parent to become unresponsive, effectively causing a denial of service (DoS) for those operations.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · updated 2026-09-15 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89767.json)\n\n**kernel: ovl: fix double end_creating() on the casefold-mismatch path** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-15.\n\nNot affected:\n\n- Red Hat Enterprise Linux 10\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\nRefer to the advisory for fix availability.","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":202952,"id":"CVE-2026-89767","ts":1789403733090,"field":"cvss","old":"7.8","new":"5.5"},{"seq":202951,"id":"CVE-2026-89767","ts":1789403733090,"field":"severity","old":"high","new":"medium"},{"seq":197655,"id":"CVE-2026-89767","ts":1789384318267,"field":"cvss","old":"5.5","new":"7.8"},{"seq":197654,"id":"CVE-2026-89767","ts":1789384318267,"field":"severity","old":"medium","new":"high"},{"seq":183630,"id":"CVE-2026-89767","ts":1789356676175,"field":"cvss","old":"7.8","new":"5.5"},{"seq":183629,"id":"CVE-2026-89767","ts":1789356676175,"field":"severity","old":"high","new":"medium"},{"seq":153656,"id":"CVE-2026-89767","ts":1789285351812,"field":"cvss","old":null,"new":"7.8"},{"seq":153655,"id":"CVE-2026-89767","ts":1789285351812,"field":"severity","old":"none","new":"high"},{"seq":147205,"id":"CVE-2026-89767","ts":1789270201114,"field":"cvss","old":null,"new":"5.5"},{"seq":147204,"id":"CVE-2026-89767","ts":1789270201114,"field":"severity","old":"none","new":"medium"},{"seq":108962,"id":"CVE-2026-89767","ts":1789183729750,"field":"cvss","old":null,"new":"5.5"},{"seq":108961,"id":"CVE-2026-89767","ts":1789183729750,"field":"severity","old":"none","new":"medium"}]}