CVE-2026-0257
Palo Alto Networks PAN-OS Authentication Bypass Vulnerability
Palo Alto Networks PAN-OS
Authentication bypass vulnerabilities in the GlobalProtect portal and gateway of Palo Alto Networks PAN-OS® software allows the attacker to bypass security restrictions and establish an unauthorized VPN connection. Panorama and Cloud NGFW are not impacted by these issues.
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 29 May 2026. US federal agencies were required to remediate it by 1 June 2026. CISA records this vulnerability as known to be used in ransomware campaigns.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 93.9%, which is higher than 99.8% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Frequently asked questions
Is CVE-2026-0257 being exploited by ransomware groups?
No ransomware group in this database is currently recorded as exploiting CVE-2026-0257.
What does CVE-2026-0257 affect?
CVE-2026-0257 affects Palo Alto Networks PAN-OS. Authentication bypass vulnerabilities in the GlobalProtect portal and gateway of Palo Alto Networks PAN-OS® software allows the attacker to bypass security restrictions and establish an unauthorized VPN connection. Panorama and Cloud NGFW are not impacted by these issues.
How severe is CVE-2026-0257?
CVE-2026-0257 is rated CRITICAL with a CVSS base score of 9.1. EPSS puts the probability of exploitation in the next 30 days at 93.9%, higher than 99.8% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 1 June 2026.
How should organisations respond to CVE-2026-0257?
Apply the vendor patch for Palo Alto Networks PAN-OS as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.