CVE-2023-28099 : Exploit Details and Defense Strategies

This CVE involves a vulnerability in OpenSIPS related to the

ds_is_in_list()

function. It can lead to a crash if the function is used with an invalid IP address string, potentially affecting users depending on the data passed to the function.

Understanding CVE-2023-28099

OpenSIPS, a Session Initiation Protocol (SIP) server implementation, is impacted by a vulnerability in versions prior to 3.1.9 and 3.2.6. The issue arises when

ds_is_in_list()

is used with an invalid IP address string, causing OpenSIPS to attempt to print a string from a random address, which may result in a crash.

What is CVE-2023-28099?

The CVE-2023-28099 vulnerability in OpenSIPS occurs when the

ds_is_in_list()

function is utilized with an invalid IP address string, potentially leading to a crash. Users not using the

$si

variable as the 1st parameter may be impacted to varying degrees based on the validity of the data passed to the function.

The Impact of CVE-2023-28099

The impact of CVE-2023-28099 can range from minor to severe, depending on the input data provided to the

ds_is_in_list()

function. It could result in a crash of OpenSIPS, affecting the availability of the system.

Technical Details of CVE-2023-28099

This vulnerability is classified with the following CVSSv3.1 metrics:

Attack Complexity: High
Attack Vector: Network
Availability Impact: High
Base Score: 5.9 (Medium)
Privileges Required: None

Vulnerability Description

The vulnerability in OpenSIPS arises from improper input validation when using the

ds_is_in_list()

function, potentially leading to a system crash.

Affected Systems and Versions

The affected versions include:

OpenSIPS version < 3.1.9
OpenSIPS version >= 3.2.0, < 3.2.6

Exploitation Mechanism

Exploiting this vulnerability involves providing an invalid IP address string to the

ds_is_in_list()

function, triggering the issue in OpenSIPS.

Mitigation and Prevention

To address CVE-2023-28099, users and administrators can take the following steps:

Immediate Steps to Take

Update OpenSIPS to version 3.1.9 or 3.2.6 to apply the necessary fix for this vulnerability.
Ensure proper input validation and sanitation in the implementation of

ds_is_in_list()

to prevent potential crashes.

Long-Term Security Practices

Regularly monitor for security advisories and updates from OpenSIPS to stay informed about potential vulnerabilities.
Implement best practices for input validation and error handling in SIP server configurations to enhance overall system security.

Patching and Updates

OpenSIPS has released fixes for this vulnerability in versions 3.1.9 and 3.2.6. It is recommended to promptly update to these versions to mitigate the risk associated with CVE-2023-28099.