CVE-2023-41329 : Exploit Details and Defense Strategies

A critical vulnerability has been discovered in WireMock and WireMock Studio, allowing attackers to bypass domain restrictions via DNS Rebinding. Find out more about the impact, technical details, and mitigation steps below.

Understanding CVE-2023-41329

WireMock and WireMock Studio are affected by a flaw that enables attackers to bypass domain restrictions through DNS Rebinding.

What is CVE-2023-41329?

The vulnerability in WireMock and WireMock Studio allows attackers to exploit a race condition triggered by a DNS server address expiration, leading to a network request going to a prohibited domain.

The Impact of CVE-2023-41329

This vulnerability has a high execution complexity, requiring control over a DNS service. However, it poses a limited impact due to the requirement for specific conditions to be met.

Technical Details of CVE-2023-41329

The issue arises from a logic defect in the domain name-based network restrictions configuration of WireMock, leaving it vulnerable to DNS rebinding attacks.

Vulnerability Description

The vulnerability stems from a race condition between initial validation and outbound network requests to blocked domains, requiring DNS server manipulation for exploitation.

Affected Systems and Versions

WireMock versions prior to 3.0.3 and wiremock-jre8 versions below 2.35.1 are affected, along with specific instances of wiremock/wiremock Docker containers and the Python version of WireMock.

Exploitation Mechanism

Attackers exploit the logic defect in WireMock's domain-based restrictions via DNS rebinding attacks, necessitating control over a DNS service for successful execution.

Mitigation and Prevention

To mitigate the risks associated with CVE-2023-41329, immediate actions and long-term security practices are recommended.

Immediate Steps to Take

Users are strongly advised to upgrade affected WireMock versions to the patched releases to prevent DNS rebinding attacks. If upgrading is not feasible, configuring firewall rules or using IP addresses instead of domain names in WireMock settings are alternative preventive measures.

Long-Term Security Practices

Implementing robust network security measures, monitoring DNS activity, and staying informed about security patches and updates are essential for maintaining security against DNS rebinding attacks.

Patching and Updates

Ensure timely installation of security patches provided by WireMock to address the vulnerability and enhance the security posture of your systems.