{"id":"CVE-2026-89682","title":"kernel: nfsd: fix fcache_disposal UAF by inlining dispose state into nfsd_net (CVE-2026-89682)","summary":"A flaw was found in the Linux kernel's NFS daemon (nfsd) component. The nfsd_file_dispose_list_delayed() function, responsible for deferring file disposal, uses a separately allocated structure for its freeme queue. During network namespac…","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-825","vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","affected":["enterprise_linux 10","enterprise_linux 9","openshift_container_platform 4"],"published":"2026-09-11","updated":"2026-09-14","sourceUpdated":"2026-09-14T08:28:55+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89682.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89682.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89682"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532019"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89682"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89682"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89682.mbox"},{"url":"https://git.kernel.org/stable/c/ba0ee9e04b7a0356c28d5a2fe445db675d24e572"},{"url":"https://git.kernel.org/stable/c/cadc9036d5a8209f89e7026ddba7cfb1c716b03c"},{"url":"https://git.kernel.org/stable/c/bbf13732f74351d21c5e0e8dd9bd8e1c48dc35d4"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.00397,"epssPercentile":0.33669,"scores":{"vendor":7,"cna":8.1},"ingestedAt":"2026-09-14T15:23:07.473Z","slug":"CVE-2026-89682","body":"## Overview\n\nA flaw was found in the Linux kernel's NFS daemon (nfsd) component. The nfsd_file_dispose_list_delayed() function, responsible for deferring file disposal, uses a separately allocated structure for its freeme queue. During network namespace teardown, this structure can be prematurely freed. This allows other kernel callbacks to attempt to dereference the freed memory, leading to a use-after-free (UAF) vulnerability. A local attacker could potentially exploit this to cause a system crash or escalate privileges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-09-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89682.json)\n\n**kernel: nfsd: fix fcache_disposal UAF by inlining dispose state into nfsd_net** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-14.\n\nAffected:\n\n- Red Hat Enterprise Linux 10\n- Red Hat Enterprise Linux 9\n- Red Hat OpenShift Container Platform 4\n\nNo fix planned:\n\n- Red Hat Enterprise Linux 10\n- Red Hat Enterprise Linux 9\n- Red Hat OpenShift Container Platform 4\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 OpenShift Container Platform 4\n\n## Remediation\n\nAffected","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":38.5,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":202805,"id":"CVE-2026-89682","ts":1789403724658,"field":"cvss","old":"8.1","new":"7"},{"seq":197746,"id":"CVE-2026-89682","ts":1789384318675,"field":"cvss","old":"6.6","new":"8.1"},{"seq":197745,"id":"CVE-2026-89682","ts":1789384318675,"field":"severity","old":"medium","new":"high"},{"seq":183679,"id":"CVE-2026-89682","ts":1789356676916,"field":"cvss","old":"8.1","new":"6.6"},{"seq":183678,"id":"CVE-2026-89682","ts":1789356676916,"field":"severity","old":"high","new":"medium"},{"seq":153556,"id":"CVE-2026-89682","ts":1789285351269,"field":"cvss","old":null,"new":"8.1"},{"seq":153555,"id":"CVE-2026-89682","ts":1789285351269,"field":"severity","old":"none","new":"high"},{"seq":109638,"id":"CVE-2026-89682","ts":1789183732745,"field":"cvss","old":null,"new":"6.6"},{"seq":109637,"id":"CVE-2026-89682","ts":1789183732745,"field":"severity","old":"none","new":"medium"}]}