CVE-2020-11582 : Vulnerability Insights and Analysis

An issue was discovered in Pulse Secure Pulse Connect Secure (PCS) through 2020-04-06. The applet in tncc.jar, executed on macOS, Linux, and Solaris clients when a Host Checker policy is enforced, launches a TCP server that accepts local connections on a random port. This can be reached by local HTTP clients, because up to 25 invalid lines are ignored, and because DNS rebinding can occur. (This server accepts, for example, a setcookie command that might be relevant to CVE-2020-11581 exploitation.)

Understanding CVE-2020-11582

This CVE identifies a vulnerability in Pulse Secure Pulse Connect Secure (PCS) that allows the execution of a TCP server on specific operating systems when a Host Checker policy is enforced, potentially leading to security risks.

What is CVE-2020-11582?

The vulnerability in Pulse Secure Pulse Connect Secure (PCS) enables the launch of a TCP server on macOS, Linux, and Solaris clients, creating a potential security loophole for local HTTP clients.

The Impact of CVE-2020-11582

The vulnerability could be exploited by malicious actors to launch a TCP server on affected systems, potentially leading to unauthorized access and security breaches.

Technical Details of CVE-2020-11582

This section provides detailed technical insights into the vulnerability.

Vulnerability Description

The issue arises from the execution of an applet in tncc.jar, allowing the launch of a TCP server on macOS, Linux, and Solaris clients under specific conditions.

Affected Systems and Versions

Operating Systems: macOS, Linux, Solaris
Pulse Secure Pulse Connect Secure (PCS) versions through 2020-04-06

Exploitation Mechanism

Launching a TCP server that accepts local connections on a random port
Accessibility by local HTTP clients due to ignored invalid lines and potential DNS rebinding

Mitigation and Prevention

Protecting systems from CVE-2020-11582 requires immediate actions and long-term security practices.

Immediate Steps to Take

Apply security patches provided by Pulse Secure
Monitor network traffic for any suspicious activity
Implement Host Checker policies to restrict unauthorized access

Long-Term Security Practices

Regularly update and patch Pulse Secure Pulse Connect Secure (PCS)
Conduct security audits and assessments to identify vulnerabilities
Educate users on safe browsing practices and potential risks

Patching and Updates

Stay informed about security advisories from Pulse Secure
Apply recommended patches promptly to mitigate the vulnerability