{"id":"CVE-2026-89540","title":"kernel: sunrpc: init gssp_lock before publishing proc entry (CVE-2026-89540)","summary":"A flaw was found in the Linux kernel's sunrpc component. A race condition exists where the `gssp_lock` mutex is not initialized before its associated `/proc/net/rpc/use-gss-proxy` entry is published. This allows a local attacker to trigger…","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-909","vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","affected":["enterprise_linux 10","enterprise_linux 6","enterprise_linux 7","enterprise_linux 8","enterprise_linux 9","openshift_container_platform 4"],"published":"2026-09-11","updated":"2026-09-15","sourceUpdated":"2026-09-15T18:29:36+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89540.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89540.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89540"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532132"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89540"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89540"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89540.mbox"},{"url":"https://git.kernel.org/stable/c/159a4fab7170badd6c4a553aef81cac079d6f4ee"},{"url":"https://git.kernel.org/stable/c/b3526ae3351968f6726bcbe25d8d09973ad79109"},{"url":"https://git.kernel.org/stable/c/7f5bcdc8da15077ebe846c2756a5a17741021410"},{"url":"https://git.kernel.org/stable/c/89c8e0733e8c46b7973503f15b1b31a8587d8030"},{"url":"https://git.kernel.org/stable/c/f15b87521168c2a92cb1931f532cba422f856f01"},{"url":"https://git.kernel.org/stable/c/edeefb111d6181a4aa278f415b005efe284b9489"},{"url":"https://git.kernel.org/stable/c/3f019571928b269feebcff59926ec13294215e0e"},{"url":"https://git.kernel.org/stable/c/5ce1ed6159731a41fdd0b03eedbed4e147036a5a"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.00176,"epssPercentile":0.06306,"scores":{"vendor":7,"cna":7.8},"ingestedAt":"2026-09-14T15:23:07.452Z","slug":"CVE-2026-89540","body":"## Overview\n\nA flaw was found in the Linux kernel's sunrpc component. A race condition exists where the `gssp_lock` mutex is not initialized before its associated `/proc/net/rpc/use-gss-proxy` entry is published. This allows a local attacker to trigger a scenario where multiple writers can concurrently access the `set_gssp_clnt()` function, leading to a denial of service for the first writer's client and a resource leak.\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 7, Red Hat Enterprise Linux 8, 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 7, Red Hat Enterprise Linux 8, … · updated 2026-09-15 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89540.json)\n\n**kernel: sunrpc: init gssp_lock before publishing proc entry** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-15.\n\nAffected:\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\nNo fix planned:\n\n- Red Hat Enterprise Linux 6\n- Red Hat Enterprise Linux 10\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":205534,"id":"CVE-2026-89540","ts":1789576724345,"field":"cvss","old":"7.8","new":"7"},{"seq":197961,"id":"CVE-2026-89540","ts":1789384321160,"field":"cvss","old":"4.1","new":"7.8"},{"seq":197960,"id":"CVE-2026-89540","ts":1789384321160,"field":"severity","old":"medium","new":"high"},{"seq":183488,"id":"CVE-2026-89540","ts":1789356675576,"field":"cvss","old":"7.8","new":"4.1"},{"seq":183487,"id":"CVE-2026-89540","ts":1789356675576,"field":"severity","old":"high","new":"medium"},{"seq":153338,"id":"CVE-2026-89540","ts":1789285350105,"field":"cvss","old":null,"new":"7.8"},{"seq":153337,"id":"CVE-2026-89540","ts":1789285350105,"field":"severity","old":"none","new":"high"},{"seq":147714,"id":"CVE-2026-89540","ts":1789270211989,"field":"cvss","old":null,"new":"4.1"},{"seq":147713,"id":"CVE-2026-89540","ts":1789270211989,"field":"severity","old":"none","new":"medium"},{"seq":109478,"id":"CVE-2026-89540","ts":1789183732070,"field":"cvss","old":null,"new":"4.1"},{"seq":109477,"id":"CVE-2026-89540","ts":1789183732070,"field":"severity","old":"none","new":"medium"}]}