{"id":"CVE-2026-89684","title":"kernel: nfsd: fix cpntf publish race in nfs4_init_cp_state (CVE-2026-89684)","summary":"A flaw was found in the Linux kernel's nfsd component. A remote attacker, by sending a specially crafted OFFLOAD_CANCEL request, could exploit a race condition during the initialization of copy state notifications. This could lead to a den…","severity":"medium","cvss":5.3,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","cvssSource":"vendor","cwe":["CWE-416","CWE-824"],"vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","affected":["enterprise_linux 10","enterprise_linux 6","enterprise_linux 9","openshift_container_platform 4"],"published":"2026-09-11","updated":"2026-10-21","sourceUpdated":"2026-10-21T10:02:11+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89684.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89684.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89684"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532088"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89684"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89684"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89684.mbox"},{"url":"https://kernelcve.org/list/?q=CVE-2026-89684"},{"url":"https://git.kernel.org/stable/c/63e18fc65587fd3f7b4c6d70e96d32fc41d82ba3"},{"url":"https://git.kernel.org/stable/c/6ac469a274e3c7d87fc46ba46d83b95009680407"},{"url":"https://git.kernel.org/stable/c/8eeca993357a0bc35aaefebfd7462ac7b0a21d9a"},{"url":"https://git.kernel.org/stable/c/bfeac42d9074e539bacd1898dd8c14b7f5776620"},{"url":"https://git.kernel.org/stable/c/21d6c5957f5ca97d7352e60f55ea412beb9419f5"},{"url":"https://git.kernel.org/stable/c/a631a26a8777bb235eabd478bbbaf26a4db750bf"},{"url":"https://git.kernel.org/stable/c/c7270f62e7a05a2ee68aa2b74262b658a14463bd"},{"url":"https://git.kernel.org/stable/c/be3a5c1d857b0dcbc11796cea603ef25834f75b2"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.00501,"epssPercentile":0.42714,"scores":{"vendor":7,"cna":7.5},"ingestedAt":"2026-09-14T15:23:07.450Z","slug":"CVE-2026-89684","body":"## Overview\n\nA flaw was found in the Linux kernel's nfsd component. A remote attacker, by sending a specially crafted OFFLOAD_CANCEL request, could exploit a race condition during the initialization of copy state notifications. This could lead to a denial of service (DoS) by causing the server to crash.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-10-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89684.json)\n\n**kernel: nfsd: fix cpntf publish race in nfs4_init_cp_state** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-10-21.\n\nAffected:\n\n- Red Hat Enterprise Linux 10\n- Red Hat Enterprise Linux 6\n- Red Hat Enterprise Linux 9\n- Red Hat OpenShift Container Platform 4\n\nNo fix planned:\n\n- Red Hat Enterprise Linux 6\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 7\n- Red Hat Enterprise Linux 8\n- Red Hat OpenShift Container Platform 4\n\n## Remediation\n\nOut of support scope\n\nWorkarounds / mitigations:\n\n- Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.","depth":"sunlit","depthScore":29,"depthScoreParts":{"impact":29.2,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":226994,"id":"CVE-2026-89684","ts":1792584972383,"field":"cvss","old":"7.5","new":"5.3"},{"seq":226993,"id":"CVE-2026-89684","ts":1792584972383,"field":"severity","old":"high","new":"medium"},{"seq":224622,"id":"CVE-2026-89684","ts":1792401441001,"field":"cvss","old":"7","new":"7.5"},{"seq":208475,"id":"CVE-2026-89684","ts":1790005711529,"field":"cvss","old":"7.5","new":"7"},{"seq":183359,"id":"CVE-2026-89684","ts":1789356675036,"field":"cvss","old":"7.5","new":"5.3"},{"seq":183358,"id":"CVE-2026-89684","ts":1789356675036,"field":"severity","old":"high","new":"medium"},{"seq":153558,"id":"CVE-2026-89684","ts":1789285351277,"field":"cvss","old":null,"new":"7.5"},{"seq":153557,"id":"CVE-2026-89684","ts":1789285351277,"field":"severity","old":"none","new":"high"},{"seq":147692,"id":"CVE-2026-89684","ts":1789270211904,"field":"cvss","old":null,"new":"5.3"},{"seq":147691,"id":"CVE-2026-89684","ts":1789270211904,"field":"severity","old":"none","new":"medium"},{"seq":109444,"id":"CVE-2026-89684","ts":1789183731938,"field":"cvss","old":null,"new":"5.3"},{"seq":109443,"id":"CVE-2026-89684","ts":1789183731938,"field":"severity","old":"none","new":"medium"}]}