CVE-2020-8260 in Pulse Connect Secure
Summary
by MITRE • 10/28/2020
A vulnerability in the Pulse Connect Secure < 9.1R9 admin web interface could allow an authenticated attacker to perform an arbitrary code execution using uncontrolled gzip extraction.
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Analysis
by VulDB Data Team • 12/17/2025
The vulnerability identified as CVE-2020-8260 affects the Pulse Connect Secure appliance version 9.1R9 and earlier, representing a critical security flaw within the administrative web interface. This issue stems from improper handling of gzip compressed data during extraction processes, creating a pathway for authenticated attackers to execute arbitrary code on the affected system. The vulnerability specifically targets the administrative interface, which provides access to critical system configuration and management functions, making it particularly dangerous for organizations relying on this secure access solution for remote connectivity.
The technical root cause of this vulnerability lies in the insecure processing of gzip compressed data within the administrative web interface components. When the system processes gzip compressed content, it fails to properly validate or sanitize the decompression parameters, allowing an attacker to craft malicious compressed data that, upon extraction, triggers unintended code execution. This flaw aligns with CWE-427 Uncontrolled Search Path Element and CWE-770 Allocation of Resources Without Limits or Throttling, as the system does not properly limit or control the resource consumption during decompression operations. The vulnerability enables attackers to bypass normal authentication mechanisms since they only need valid administrative credentials to exploit the issue.
The operational impact of CVE-2020-8260 extends beyond simple code execution, as it provides attackers with full administrative control over the Pulse Connect Secure appliance. This compromise allows unauthorized individuals to modify system configurations, access encrypted communications, manipulate user access controls, and potentially pivot to other systems within the network. The vulnerability's exploitation requires only authenticated access, which significantly reduces the attack surface compared to unauthenticated exploits. However, this still represents a severe risk for organizations where administrative credentials might be compromised through phishing, credential theft, or other means, as demonstrated by ATT&CK technique T1078 Valid Accounts and T1566 Phishing.
Organizations affected by this vulnerability should immediately implement the vendor-provided security patches and updates to remediate the issue. The fix typically involves updating the Pulse Connect Secure appliance to version 9.1R9 or later, which includes proper input validation and secure decompression handling for gzip data. Additional mitigations include implementing network segmentation to limit access to the administrative interface, enforcing strict access controls and monitoring for suspicious administrative activities, and conducting thorough credential hygiene practices. Security teams should also consider deploying intrusion detection systems to monitor for potential exploitation attempts and maintain comprehensive audit logs of administrative activities. The vulnerability highlights the importance of proper resource management and input validation in web applications, particularly those handling compressed data, and serves as a reminder of the critical nature of maintaining up-to-date security patches across all network infrastructure components.