{"id":"CVE-2026-98586","title":"kernel: sctp: hold asoc or transport before mod_timer() in timer handlers (CVE-2026-98586)","summary":"A flaw was found in the Linux kernel's Stream Control Transmission Protocol (SCTP) subsystem. This vulnerability can lead to a Denial of Service (DoS) through a kernel crash. A race condition occurs between timer rearming and cleanup opera…","severity":"medium","cvss":5.9,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","cvssSource":"vendor","cwe":"CWE-911","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":"2026-10-18","updated":"2026-10-20","sourceUpdated":"2026-10-20T04:11:03+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98586.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98586.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-98586"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2555030"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98586"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98586"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98586.mbox"},{"url":"https://git.kernel.org/stable/c/f7dea7eaea20fe9b80f8f77ba44d02b4a17f8050"},{"url":"https://git.kernel.org/stable/c/f9d929026d487a988bfa12c065f892e823e5b6ab"},{"url":"https://git.kernel.org/stable/c/9d3d39da054476e7aa05cd877b93ca73a9a77434"},{"url":"https://git.kernel.org/stable/c/27c51a9b55b227309161c903f9ecfbf022516bc2"},{"url":"https://git.kernel.org/stable/c/d18cb8fd1b6ba95c85de644203cfe1b071ff0c0f"},{"url":"https://git.kernel.org/stable/c/35bf3b23c9a871f44c1453d85f8332be4e088dda"},{"url":"https://git.kernel.org/stable/c/cae23ae3f7887a1cf8a75da38edcebeef695040f"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.00173,"epssPercentile":0.06622,"ingestedAt":"2026-10-18T15:45:12.252Z","slug":"CVE-2026-98586","body":"## Overview\n\nA flaw was found in the Linux kernel's Stream Control Transmission Protocol (SCTP) subsystem. This vulnerability can lead to a Denial of Service (DoS) through a kernel crash. A race condition occurs between timer rearming and cleanup operations because the system modifies a timer before properly acquiring a reference to the associated transport object. An attacker able to generate SCTP traffic can trigger this timing window, causing a reference count underflow on an already freed memory object and resulting in system instability.\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 2026-10-20 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98586.json)\n\n**kernel: sctp: hold asoc or transport before mod_timer() in timer handlers** — rated Moderate by Red Hat. Released 2026-10-18, updated 2026-10-20.\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":"sunlit","depthScore":32,"depthScoreParts":{"impact":32.5,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":225751,"id":"CVE-2026-98586","ts":1792498432057,"field":"cvss","old":null,"new":"5.9"},{"seq":225750,"id":"CVE-2026-98586","ts":1792498432057,"field":"severity","old":"none","new":"medium"}]}