Authentication bypass affecting Palo Alto Networks PAN-OS

PAN-OS is the operating system for Palo Alto Networks' next-generation firewalls, used to secure corporate networks, in particular via the GlobalProtect component for VPN access. This system is affected by a vulnerability labeled CVE-2026-0257 resulting from the lack of validation and integrity control of authentication cookies. Exploitation of this vulnerability would allow an unauthenticated attacker to forge a valid cookie to bypass security controls and establish an unauthorized VPN session to the internal network. It is classified critical with a severity score of 9.1 according to CVSS V3.1.

• PAN-OS 10.2 versions prior to 10.2.7-h34, 10.2.10-h36, 10.2.13-h21, 10.2.16-h7, and 10.2.18-h6;
• PAN-OS 11.1 versions prior to 11.1.4-h33, 11.1.6-h32, 11.1.7-h6, 11.1.10-h25, 11.1.13-h5 and 11.1.15;
• PAN-OS 11.2 versions prior to 11.2.4-h17, 11.2.7-h14, 11.2.10-h7 and 11.2.12;
• PAN-OS 12.1 versions prior to 12.1.4-h6 and 12.1.7;
• Prisma Access 11.2.0 versions prior to 11.2.7-h13;
• Prisma Access 10.2.0 versions prior to 10.2.10-h36;