CVE-2023-27598 : Security Advisory and Response

This CVE involves a vulnerability in OpenSIPS where the

parse_via()

function is affected, leading to a high severity denial of service risk due to a segmentation fault triggered by a specially crafted

Via

header in versions prior to 3.1.7 and 3.2.4.

Understanding CVE-2023-27598

This section will delve into the specifics of CVE-2023-27598, its impact, technical details, and mitigation strategies.

What is CVE-2023-27598?

The vulnerability in OpenSIPS revolves around an issue triggered by sending a malformed

Via

header to the server, resulting in a segmentation fault when the

calc_tag_suffix

function is invoked. This fault occurs due to uninitialized strings being passed to the

MD5StringArray

function, leading to a crash. Exploiting this vulnerability can result in a denial of service attack.

The Impact of CVE-2023-27598

The impact of CVE-2023-27598 is classified as high, primarily due to the potential for a denial of service attack resulting from a specially crafted

Via

header triggering a segmentation fault in OpenSIPS versions earlier than 3.1.7 and 3.2.4. However, further exploitation beyond a crash is not believed to be feasible as the uninitialized string points to memory location

0x0

.

Technical Details of CVE-2023-27598

In this section, we will explore the vulnerability description, affected systems and versions, as well as the exploitation mechanism related to CVE-2023-27598.

Vulnerability Description

The vulnerability arises from an issue in the

parse_via()

function of OpenSIPS that allows for the triggering of a segmentation fault by sending a malformed

Via

header.

Affected Systems and Versions

The vulnerability impacts OpenSIPS versions prior to 3.1.7 and 3.2.4. Specifically, versions

< 3.1.7

and

>= 3.2.0, < 3.2.4

are affected by this vulnerability.

Exploitation Mechanism

Exploiting this vulnerability involves sending a specially crafted

Via

header that is parsed as correct but leads to the passing of uninitialized strings to a function, resulting in a crash and potential denial of service.

Mitigation and Prevention

Understanding how to mitigate and prevent the exploitation of CVE-2023-27598 is crucial for ensuring system security.

Immediate Steps to Take

To address this vulnerability, it is recommended to update OpenSIPS to versions 3.1.7 and 3.2.4, where the issue has been resolved. Additionally, monitoring network activities for any anomalous

Via

headers can help in early detection and prevention of potential attacks.

Long-Term Security Practices

To enhance overall security posture, organizations should regularly update software and apply patches promptly to mitigate known vulnerabilities. Implementing a robust network security policy and conducting regular security audits can help in identifying and addressing potential risks proactively.

Patching and Updates

Ensuring that OpenSIPS is regularly updated to the latest versions is crucial for maintaining a secure environment. Applying patches provided by the vendor promptly after release can help in closing security gaps and preventing exploitation of known vulnerabilities.