CVE-2020-2018: 
PAN-OS vulnerability analysis and mitigation

An authentication bypass vulnerability (CVE-2020-2018) was discovered in the Panorama context switching feature of Palo Alto Networks' PAN-OS. The vulnerability was disclosed on May 13, 2020, affecting multiple versions of PAN-OS including versions earlier than 7.1.26, 8.1.12, and 9.0.6. This critical severity vulnerability allows an attacker with network access to a Panorama's management interface to gain privileged access to managed firewalls (Palo Alto Advisory).

The vulnerability has been assigned a CVSS v3.1 Base Score of 9.0 (Critical) with the following metrics: Attack Vector: Network, Attack Complexity: High, Privileges Required: None, User Interaction: None, Scope: Changed, Confidentiality Impact: High, Integrity Impact: High, Availability Impact: High. The vulnerability is classified as CWE-287 (Improper Authentication). The issue requires some knowledge of managed firewalls to exploit and does not affect Panorama configured with custom certificates authentication for communication between Panorama and managed devices (Palo Alto Advisory).

If successfully exploited, this vulnerability allows an attacker to gain privileged access to managed firewalls through the Panorama management interface. The high severity rating across confidentiality, integrity, and availability impacts indicates that successful exploitation could result in complete compromise of the affected systems (Palo Alto Advisory).

The vulnerability requires network access to a Panorama's management interface and some knowledge of managed firewalls to exploit. The attack complexity is rated as high, but no privileges are required, and no user interaction is needed for exploitation (Palo Alto Advisory).

The vulnerability has been fixed in PAN-OS versions 7.1.26, 8.1.12, 9.0.6, and all later versions. Upgrading Panorama to a fixed version is sufficient to resolve the issue. Additionally, the vulnerability can be completely mitigated by enabling custom certificates authentication between Panorama and managed firewalls. Organizations are advised to follow best practices for securing the PAN-OS management interface (Palo Alto Advisory).

The vulnerability was discovered by Ben Nott of Palo Alto Networks during an internal security review (Palo Alto Advisory).