CVE-2020-2017 in PAN-OS
Summary
by MITRE
A DOM-Based Cross Site Scripting Vulnerability exists in PAN-OS and Panorama Management Web Interfaces. A remote attacker able to convince an authenticated administrator to click on a crafted link to PAN-OS and Panorama Web Interfaces could execute arbitrary JavaScript code in the administrator's browser and perform administrative actions. This issue affects: PAN-OS 7.1 versions earlier than 7.1.26; PAN-OS 8.0 versions earlier than 8.0.21; PAN-OS 8.1 versions earlier than 8.1.13; PAN-OS 9.0 versions earlier than 9.0.6.
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Analysis
by VulDB Data Team • 10/17/2020
This vulnerability represents a critical dom-based cross site scripting flaw that specifically targets the web management interfaces of Palo Alto Networks firewalls and Panorama management systems. The issue stems from improper input validation and sanitization within the web application's javascript code, where user-supplied parameters are directly incorporated into the document object model without adequate escaping or encoding. The vulnerability affects multiple major versions of PAN-OS including 7.1, 8.0, 8.1, and 9.0, with specific patched versions outlined in the advisory. This type of vulnerability falls under the CWE-79 category of Cross Site Scripting, specifically classified as DOM-based XSS where the attack vector manipulates the DOM environment rather than server-side content. The attack requires social engineering to trick authenticated administrators into clicking malicious links, making it particularly dangerous as it leverages the trust relationship between the user and the system.
The operational impact of this vulnerability is severe as it allows remote attackers to execute arbitrary javascript code within the context of an authenticated administrator's browser session. This privilege escalation capability means attackers can perform administrative actions such as modifying firewall rules, accessing sensitive configuration data, creating new user accounts, or even exfiltrating data from the network. The vulnerability specifically targets management interfaces, which are typically accessed by authorized personnel with elevated privileges, making the potential damage significantly greater than typical user-facing XSS vulnerabilities. The attack requires minimal technical sophistication from the adversary since it only requires convincing a legitimate administrator to click a malicious link, which can be achieved through phishing campaigns or compromised websites. This makes the vulnerability particularly concerning for enterprise environments where administrators frequently interact with web-based management interfaces.
Mitigation strategies for this vulnerability should include immediate deployment of the vendor-supplied patches for affected PAN-OS versions, as well as implementing comprehensive monitoring for suspicious web traffic patterns and user behavior anomalies. Network segmentation and privilege separation can help limit the potential impact if an administrator's session is compromised. Organizations should also conduct thorough security awareness training for administrators to recognize social engineering attempts and suspicious links. The vulnerability demonstrates the importance of proper input validation in web applications and highlights the need for defense-in-depth strategies that protect not just the network perimeter but also the management interfaces that provide administrative access to critical infrastructure. Security teams should implement web application firewalls and content security policies to detect and prevent exploitation attempts. The ATT&CK framework categorizes this vulnerability under T1059.007 for command and scripting interpreter and T1566 for phishing, emphasizing both the execution and initial access components of the attack chain. Regular security assessments and penetration testing should include verification of input sanitization mechanisms in web applications to prevent similar vulnerabilities from being introduced in future development cycles.