{"id":"CVE-2026-98773","title":"kernel: USB: cdc-acm: skip URB restart in port_shutdown if disconnected (CVE-2026-98773)","summary":"A flaw was found in the Linux kernel's CDC ACM (Communications Device Class Abstract Control Model) USB driver. A timing race condition during device disconnection and port closure can lead to a use-after-free vulnerability when communicat…","severity":"medium","cvss":4.7,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","cvssSource":"vendor","cwe":"CWE-825","vendor":"Red Hat","product":"Red Hat Enterprise Linux 6","affected":["enterprise_linux 6"],"published":"2026-10-18","updated":"2026-10-23","sourceUpdated":"2026-10-23T08:07:15+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98773.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98773.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-98773"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2555078"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98773"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98773"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98773.mbox"},{"url":"https://git.kernel.org/stable/c/d86775e79838d7d2e38ccf506a7d0f8e2dd4d5d0"},{"url":"https://git.kernel.org/stable/c/9742905d9ed5bf23ebe4c100dec80b6bc50fb522"},{"url":"https://git.kernel.org/stable/c/a0ed07b5bbb2d8fcef86810453216070691816e7"},{"url":"https://git.kernel.org/stable/c/420ca35af891d33522cc08504768ccd60a4c450a"},{"url":"https://git.kernel.org/stable/c/dc614d6bc991740d41d5a99ac7765c4b675dda88"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.00168,"epssPercentile":0.05977,"ingestedAt":"2026-10-18T16:47:32.491Z","slug":"CVE-2026-98773","body":"## Overview\n\nA flaw was found in the Linux kernel's CDC ACM (Communications Device Class Abstract Control Model) USB driver. A timing race condition during device disconnection and port closure can lead to a use-after-free vulnerability when communication requests attempt to access already freed memory buffers. A local attacker could exploit this flaw to cause a Denial of Service (DoS) via a system crash or potentially achieve privilege escalation.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 6 · no fix planned: Red Hat Enterprise Linux 6 · updated 2026-10-23 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98773.json)\n\n**kernel: USB: cdc-acm: skip URB restart in port_shutdown if disconnected** — rated Moderate by Red Hat. Released 2026-10-18, updated 2026-10-23.\n\nAffected:\n\n- Red Hat Enterprise Linux 6\n\nNo fix planned:\n\n- Red Hat Enterprise Linux 6\n\nNot affected:\n\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":26,"depthScoreParts":{"impact":25.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":228139,"id":"CVE-2026-98773","ts":1792758128868,"field":"cvss","old":null,"new":"4.7"},{"seq":228138,"id":"CVE-2026-98773","ts":1792758128868,"field":"severity","old":"none","new":"medium"}]}