{"id":"CVE-2026-93866","title":"Fireware OS Pre-Authentication Integer Overflow in Access Portal Allows Out-of-Bounds Write","summary":"An integer overflow vulnerability in the WebSocket connection handling used by WatchGuard Fireware OS's Access Portal allows a remote, unauthenticated attacker to write beyond the bounds of a heap buffer by sending a specially crafted re…","severity":"critical","cvss":9.2,"cvssVector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","cvssSource":"cna","cwe":["CWE-190","CWE-288","CWE-787"],"vendor":"WatchGuard","product":"Fireware OS","affected":["fireware_os >= 2025.1 < 2026.4","fireware_os >= 12.0 < 12.12.4","fireware_os >= 12.0 < 12.5.22"],"published":"2026-10-27","updated":"2026-10-27","sourceUpdated":"2026-10-27T15:52:27.871Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-93866","references":[{"url":"https://psirt.watchguard.com/CVE-2026-93866"}],"tags":["cve.org"],"ingestedAt":"2026-10-27T16:11:59.475Z","slug":"CVE-2026-93866","body":"## Overview\n\nAn integer overflow vulnerability in the WebSocket connection handling used by WatchGuard Fireware OS's Access Portal allows a remote, unauthenticated attacker to write beyond the bounds of a heap buffer by sending a specially crafted request while the Access Portal feature is enabled.\n\n## Affected\n\n- `fireware_os >= 2025.1 < 2026.4`\n- `fireware_os >= 12.0 < 12.12.4`\n- `fireware_os >= 12.0 < 12.5.22`\n\n## Remediation\n\nFireware OS 2026.4, Fireware OS 12.12.4, Fireware OS 12.5.22","depth":"midnight","depthScore":51,"depthScoreParts":{"impact":50.6,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}