CVE-2026-0257: Palo Alto Networks PAN-OS Authentication Bypass Vulnerability

CVE-2026-0257: high vulnerability affecting PAN-OS. Check CVSS, KEV status, business impact and recommended administrator actions.
CVE-2026-0257CVSS 7.8CISA KEVFirewall

CVE-2026-0257: Palo Alto Networks PAN-OS Authentication Bypass Vulnerability

CVE-2026-0257: high vulnerability affecting PAN-OS. Check CVSS, KEV status, business impact and recommended administrator actions.

CVSS
7.8 HIGH
EPSS
99.84%
Known exploited
yes
Product
PAN-OS

What is known

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.

Business impact

Successful exploitation of CVE-2026-0257, a high vulnerability (CVSS 7.8) affecting PAN-OS, may affect the confidentiality, integrity or availability of the vulnerable environment. The exact impact depends on the installed version, exposed interfaces and deployment configuration. CISA lists this vulnerability in the Known Exploited Vulnerabilities catalog, so exposed systems should be treated as a priority.

Recommended administrator action

Confirm whether PAN-OS is present and compare installed versions with the vendor advisory and NVD record. Apply the vendor patch or documented mitigation; until remediation is complete, reduce exposure of affected interfaces, review relevant logs and monitor for indicators of exploitation. Where applicable, include the CISA KEV remediation due date of 2026-06-01 in the change plan. DataHouse can support version verification, managed patching, network exposure reduction, log review and backup validation for dedicated, cloud and colocated environments.

Sources

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