{"id":"CVE-2026-89683","title":"kernel: nfsd: fix dentry ref leak on V4ROOT export filehandle lookup (CVE-2026-89683)","summary":"A flaw was found in the Linux kernel's nfsd (NFS daemon). A remote attacker could exploit this vulnerability by sending a specially crafted NFSv3 filehandle targeting a V4ROOT export's file system identifier (fsid). This action triggers a …","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-911","vendor":"Red Hat","product":"Red Hat Enterprise Linux 10","affected":["enterprise_linux 10","enterprise_linux 6"],"published":"2026-09-11","updated":"2026-09-16","sourceUpdated":"2026-09-16T10:08:24+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89683.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89683.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89683"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532313"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89683"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89683"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89683.mbox"},{"url":"https://git.kernel.org/stable/c/11db8df188b34bdb8c6a3a0bf438e5fc8cd75aca"},{"url":"https://git.kernel.org/stable/c/6247023fbbec1325029f2d5f2a7cdc0f9f9ea15a"},{"url":"https://git.kernel.org/stable/c/c1ae0f973bcba5730871e35976a0ab6878fdac34"},{"url":"https://git.kernel.org/stable/c/d493cf57f4c4dae5396cd6ad41e5c209d0615a81"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.00175,"epssPercentile":0.07301,"ingestedAt":"2026-09-14T11:11:19.885Z","slug":"CVE-2026-89683","body":"## Overview\n\nA flaw was found in the Linux kernel's nfsd (NFS daemon). A remote attacker could exploit this vulnerability by sending a specially crafted NFSv3 filehandle targeting a V4ROOT export's file system identifier (fsid). This action triggers a dentry reference leak, which can lead to resource exhaustion and ultimately result in a Denial of Service (DoS) on the affected system.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10 · updated 2026-09-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89683.json)\n\n**kernel: nfsd: fix dentry ref leak on V4ROOT export filehandle lookup** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-16.\n\nAffected:\n\n- Red Hat Enterprise Linux 10\n- Red Hat Enterprise Linux 6\n\nNo fix planned:\n\n- Red Hat Enterprise Linux 6\n- Red Hat Enterprise Linux 10\n\nNot affected:\n\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":205472,"id":"CVE-2026-89683","ts":1789576721417,"field":"cvss","old":"5.9","new":"7"},{"seq":205471,"id":"CVE-2026-89683","ts":1789576721417,"field":"severity","old":"medium","new":"high"},{"seq":204013,"id":"CVE-2026-89683","ts":1789490231046,"field":"cvss","old":null,"new":"5.9"},{"seq":204012,"id":"CVE-2026-89683","ts":1789490231046,"field":"severity","old":"none","new":"medium"},{"seq":147387,"id":"CVE-2026-89683","ts":1789270210704,"field":"cvss","old":null,"new":"5.9"},{"seq":147386,"id":"CVE-2026-89683","ts":1789270210704,"field":"severity","old":"none","new":"medium"},{"seq":109133,"id":"CVE-2026-89683","ts":1789183730438,"field":"cvss","old":null,"new":"5.9"},{"seq":109132,"id":"CVE-2026-89683","ts":1789183730438,"field":"severity","old":"none","new":"medium"}]}