CVE-2019-12949 : Exploit Details and Defense Strategies

A vulnerability in pfSense versions 2.4.4-p2 and 2.4.4-p3 allows attackers to execute unauthorized commands with root privileges by exploiting XSS techniques.

Understanding CVE-2019-12949

This CVE involves a security issue in pfSense versions 2.4.4-p2 and 2.4.4-p3 that enables attackers to run arbitrary commands with root privileges on a server.

What is CVE-2019-12949?

An attacker can exploit a vulnerability in pfSense versions 2.4.4-p2 and 2.4.4-p3 to execute unauthorized commands with root privileges on a targeted server. This can be achieved by tricking an authenticated administrator into interacting with a phishing page and clicking on a button. By leveraging cross-site scripting (XSS) techniques, the attacker can upload and execute arbitrary executable code on the server. The vulnerable pages that can be used for this attack are diag_command.php and rrd_fetch_json.php, specifically the timePeriod parameter.

The Impact of CVE-2019-12949

The vulnerability allows remote attackers to gain unauthorized access and execute commands with root privileges on the affected server, compromising its security and integrity.

Technical Details of CVE-2019-12949

This section provides more in-depth technical insights into the CVE.

Vulnerability Description

In pfSense 2.4.4-p2 and 2.4.4-p3, an authenticated administrator can be tricked into clicking on a button on a phishing page, enabling an attacker to use XSS to upload arbitrary executable code to the server. Subsequently, the remote attacker can execute any command with root privileges on the server.

Affected Systems and Versions

pfSense versions 2.4.4-p2 and 2.4.4-p3

Exploitation Mechanism

Attackers exploit cross-site scripting (XSS) techniques by tricking authenticated administrators into interacting with a phishing page and clicking on a button.
The vulnerable pages for this attack are diag_command.php and rrd_fetch_json.php, specifically the timePeriod parameter.

Mitigation and Prevention

Protecting systems from CVE-2019-12949 requires immediate actions and long-term security practices.

Immediate Steps to Take

Update pfSense to the latest patched version to mitigate the vulnerability.
Educate administrators about phishing attacks and the importance of not interacting with suspicious links or pages.

Long-Term Security Practices

Implement regular security training for administrators to enhance awareness of social engineering attacks.
Monitor and restrict access to critical system functions to prevent unauthorized command executions.

Patching and Updates

Apply security patches promptly to ensure that known vulnerabilities are addressed and system security is maintained.