CVE-2021-3046 in PAN-OS
Summary
by MITRE • 08/12/2021
An improper authentication vulnerability exists in Palo Alto Networks PAN-OS software that enables a SAML authenticated attacker to impersonate any other user in the GlobalProtect Portal and GlobalProtect Gateway when they are configured to use SAML authentication. This issue impacts: PAN-OS 8.1 versions earlier than PAN-OS 8.1.19; PAN-OS 9.0 versions earlier than PAN-OS 9.0.14; PAN-OS 9.1 versions earlier than PAN-OS 9.1.9; PAN-OS 10.0 versions earlier than PAN-OS 10.0.5. PAN-OS 10.1 versions are not impacted.
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Analysis
by VulDB Data Team • 08/16/2021
The vulnerability described in CVE-2021-3046 represents a critical improper authentication flaw within Palo Alto Networks PAN-OS software that specifically affects GlobalProtect Portal and GlobalProtect Gateway configurations utilizing SAML authentication mechanisms. This issue stems from a fundamental weakness in the authentication process that allows malicious actors who have already established SAML authentication to escalate their privileges and impersonate arbitrary users within the system. The vulnerability is particularly concerning because it undermines the core security principle of authentication integrity, enabling attackers to bypass normal access controls and potentially gain unauthorized access to sensitive network resources.
The technical flaw manifests in the way PAN-OS handles session management and user identity validation when SAML authentication is employed for GlobalProtect services. When an attacker successfully authenticates through SAML, the system fails to properly validate or enforce the authenticated user context, allowing them to manipulate session data or request tokens that grant access to other user accounts. This weakness creates a privilege escalation vector where a single compromised SAML session can potentially provide access to multiple user accounts within the GlobalProtect environment, effectively breaking the authentication boundary that should separate different user identities.
The operational impact of this vulnerability extends beyond simple unauthorized access, as it enables attackers to conduct sophisticated reconnaissance and lateral movement activities within the network infrastructure. An attacker who exploits this vulnerability could potentially access sensitive network data, modify user configurations, or establish persistent access points through the GlobalProtect portal. The affected PAN-OS versions span multiple major releases, indicating that this was a widespread issue affecting organizations using various generations of Palo Alto Networks firewalls. Organizations utilizing GlobalProtect with SAML authentication were particularly at risk, as the vulnerability specifically targeted the integration between SAML authentication and the GlobalProtect service.
The vulnerability aligns with CWE-287, which addresses improper authentication issues, and represents a classic case of authentication bypass that could be leveraged as part of broader attack chains within the MITRE ATT&CK framework, specifically under the credential access and privilege escalation domains. Organizations that had not patched their PAN-OS installations were exposed to potential compromise of their network access controls, as the vulnerability allowed attackers to effectively assume the identities of legitimate users without requiring additional credentials or authentication factors. The fact that PAN-OS 10.1 versions were not impacted suggests that Palo Alto Networks addressed this specific flaw in their subsequent release cycle, highlighting the importance of maintaining up-to-date security software. Security teams should prioritize immediate patching of affected systems and consider implementing additional monitoring controls to detect potential exploitation attempts, particularly focusing on unusual authentication patterns or session manipulation activities within GlobalProtect environments.