CVE-2019-9689 : Exploit Details and Defense Strategies

A Buffer Overflow vulnerability in Cameron Hamilton-Rich axTLS versions up to 2.1.5 allows attackers to exploit the process_certificate function by sending a specially crafted TLS certificate handshake message.

Understanding CVE-2019-9689

This CVE involves a security issue in the axTLS library that can lead to a Denial-of-Service attack.

What is CVE-2019-9689?

The vulnerability arises from a Buffer Overflow in the process_certificate function in tls1.c in axTLS versions up to 2.1.5, triggered by a malicious TLS certificate handshake message.

The Impact of CVE-2019-9689

Attackers can exploit this vulnerability to execute arbitrary code or crash the application by sending a crafted TLS certificate handshake message.
This could result in a Denial-of-Service condition, disrupting the availability of the affected system.

Technical Details of CVE-2019-9689

This section delves into the specifics of the vulnerability.

Vulnerability Description

The vulnerability allows for a Buffer Overflow via a specially crafted TLS certificate handshake message containing zero certificates.

Affected Systems and Versions

Product: Not applicable
Vendor: Not applicable
Versions: Up to 2.1.5 are affected

Exploitation Mechanism

Attackers can exploit the vulnerability by sending a malicious TLS certificate handshake message with zero certificates.

Mitigation and Prevention

Protecting systems from CVE-2019-9689 requires immediate actions and long-term security practices.

Immediate Steps to Take

Update axTLS to a patched version that addresses the Buffer Overflow vulnerability.
Monitor network traffic for any signs of exploitation.

Long-Term Security Practices

Regularly update software and libraries to mitigate known vulnerabilities.
Implement network segmentation to limit the impact of potential attacks.

Patching and Updates

Apply patches provided by the vendor promptly to fix the vulnerability and enhance system security.