CVE-2019-8953 : Security Advisory and Response

HAProxy package for pfSense prior to version 0.59_16 is vulnerable to cross-site scripting (XSS) attacks through specific parameters in related files.

Understanding CVE-2019-8953

This CVE involves a vulnerability in the HAProxy package used in pfSense, allowing for XSS attacks.

What is CVE-2019-8953?

The HAProxy package for pfSense before version 0.59_16 is susceptible to cross-site scripting (XSS) attacks. The issue arises from the desc and table_actionsaclN parameters in haproxy_listeners.php and haproxy_listeners_edit.php files.

The Impact of CVE-2019-8953

Attackers can exploit this vulnerability to execute malicious scripts in the context of a user's browser session.
This could lead to unauthorized actions, data theft, or further compromise of the affected system.

Technical Details of CVE-2019-8953

This section delves into the technical aspects of the vulnerability.

Vulnerability Description

The vulnerability in the HAProxy package before version 0.59_16 for pfSense allows for XSS attacks via the desc or table_actionsaclN parameters.

Affected Systems and Versions

Product: Not applicable
Vendor: Not applicable
Versions affected: Not applicable

Exploitation Mechanism

Exploitation occurs through the desc or table_actionsaclN parameters in haproxy_listeners.php and haproxy_listeners_edit.php files.

Mitigation and Prevention

Protecting systems from this vulnerability is crucial.

Immediate Steps to Take

Upgrade pfSense to version 0.59_16 or later to mitigate the XSS risk.
Monitor for any unusual activities that might indicate an ongoing attack.

Long-Term Security Practices

Regularly update and patch all software components to prevent known vulnerabilities.
Implement input validation and output encoding to mitigate XSS risks in web applications.

Patching and Updates

Stay informed about security updates for pfSense and promptly apply patches to address known vulnerabilities.