CVE-2018-12228 : Security Advisory and Response

A problem was found in the Asterisk Open Source 15.x versions prior to 15.4.1 where abrupt disconnections or specially crafted messages over TCP/TLS could lead to an endless loop, rendering the system inoperable.

Understanding CVE-2018-12228

What is CVE-2018-12228?

An issue in Asterisk Open Source 15.x versions before 15.4.1 causes the system to get stuck in a loop when trying to read data after a client disconnects or sends a specific message over TCP/TLS.

The Impact of CVE-2018-12228

This vulnerability can result in a denial of service (DoS) condition, making the affected system inoperable.

Technical Details of CVE-2018-12228

Vulnerability Description

When connected to Asterisk via TCP/TLS, abrupt client disconnections or specially crafted messages trigger an infinite loop, causing the system to become unusable.

Affected Systems and Versions

Product: Asterisk Open Source 15.x
Versions: Prior to 15.4.1

Exploitation Mechanism

Attackers can exploit this vulnerability by establishing a connection with Asterisk using TCP/TLS and abruptly disconnecting or sending a specially designed message.

Mitigation and Prevention

Immediate Steps to Take

Update Asterisk to version 15.4.1 or later to mitigate the vulnerability.
Monitor network traffic for any suspicious activities that could indicate exploitation.

Long-Term Security Practices

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

Patching and Updates

Apply security patches provided by Asterisk promptly to address this vulnerability.