CVE-2018-7286 Explained : Impact and Mitigation

A vulnerability was found in Asterisk versions 13.19.1, 14.x through 14.7.5, and 15.x through 15.2.1, as well as Certified Asterisk version 13.18-cert2. Authenticated remote users can cause Asterisk to crash by exploiting the res_pjsip module.

Understanding CVE-2018-7286

This CVE involves a vulnerability in Asterisk that allows authenticated remote users to crash the system by sending specific SIP INVITE messages.

What is CVE-2018-7286?

The vulnerability in Asterisk versions 13.19.1, 14.x through 14.7.5, and 15.x through 15.2.1, as well as Certified Asterisk version 13.18-cert2, enables authenticated remote users to trigger a segmentation fault in Asterisk by sending multiple SIP INVITE messages over a TCP or TLS connection and abruptly closing the connection.

The Impact of CVE-2018-7286

The exploitation of this vulnerability can lead to a denial of service (DoS) condition, causing Asterisk to crash and potentially disrupting communication services relying on the affected systems.

Technical Details of CVE-2018-7286

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

Vulnerability Description

The issue resides in the res_pjsip module of Asterisk, where authenticated remote users can exploit the system by sending a series of SIP INVITE messages over TCP or TLS connections and then closing the connection abruptly, resulting in a segmentation fault.

Affected Systems and Versions

Asterisk versions 13.19.1, 14.x through 14.7.5, and 15.x through 15.2.1
Certified Asterisk version 13.18-cert2

Exploitation Mechanism

Authenticated remote users can trigger the vulnerability by sending multiple SIP INVITE messages over a TCP or TLS connection and closing the connection suddenly, causing Asterisk to crash.

Mitigation and Prevention

Protecting systems from CVE-2018-7286 requires immediate actions and long-term security measures.

Immediate Steps to Take

Apply vendor patches and updates promptly to address the vulnerability.
Monitor network traffic for any suspicious activity that could indicate an ongoing exploitation attempt.

Long-Term Security Practices

Regularly update and patch Asterisk installations to mitigate known vulnerabilities.
Implement network segmentation and access controls to limit the impact of potential attacks.

Patching and Updates

Check for security advisories from Asterisk and apply patches as soon as they are available to prevent exploitation of this vulnerability.