Palo Alto Fixes GlobalProtect DoS Flaw That Can Crash Firewalls Without Login
Jan 15, 2026
Network Security / Vulnerability
Palo Alto Networks has released security updates for a high-severity security flaw impacting GlobalProtect Gateway and Portal, for which it said there exists a proof-of-concept (PoC) exploit. The vulnerability, tracked as CVE-2026-0227 (CVSS score: 7.7), has been described as a denial-of-service (DoS) condition impacting GlobalProtect PAN-OS software arising as a result of an improper check for exceptional conditions ( CWE-754 ) "A vulnerability in Palo Alto Networks PAN-OS software enables an unauthenticated attacker to cause a denial-of-service (DoS) to the firewall," the company said in an advisory released Wednesday. "Repeated attempts to trigger this issue result in the firewall entering into maintenance mode." The issue, discovered and reported by an unnamed external researcher, affects the following versions - PAN-OS 12.1 < 12.1.3-h3, < 12.1.4 PAN-OS 11.2 < 11.2.4-h15, < 11.2.7-h8, < 11.2.10-h2 PAN-OS 11.1 < 11.1.4-h27, < 11.1.6...