CVE-2021-44273 : Security Advisory and Response

CVE-2021-44273 affects e2guardian v5.4.x <= v5.4.3r due to missing SSL certificate validation, making it vulnerable to Man-in-the-Middle (MITM) attacks.

Understanding CVE-2021-44273

In this section, we will delve into the details of CVE-2021-44273.

What is CVE-2021-44273?

CVE-2021-44273 exposes a vulnerability in e2guardian where SSL MITM engine lacks SSL certificate validation. When e2guardian acts as a standalone proxy or transparent proxy with SSL MITM enabled, it fails to validate hostnames in certificates of connected web servers, leaving it susceptible to MITM attacks.

The Impact of CVE-2021-44273

The vulnerability in e2guardian poses a significant risk as it allows threat actors to intercept and manipulate communication between e2guardian and web servers, potentially leading to data breaches or unauthorized access.

Technical Details of CVE-2021-44273

Let's explore the technical aspects of CVE-2021-44273.

Vulnerability Description

The SSL MITM engine in e2guardian v5.4.x <= v5.4.3r lacks SSL certificate validation, enabling adversaries to exploit the system through MITM attacks.

Affected Systems and Versions

Affected Vendor: n/a
Affected Product: n/a
Affected Versions: e2guardian v5.4.x <= v5.4.3r

Exploitation Mechanism

The vulnerability arises when e2guardian, built with OpenSSL v1.1.x, fails to validate hostnames in web server certificates, allowing attackers to perform MITM attacks.

Mitigation and Prevention

Protecting systems from CVE-2021-44273 is crucial for maintaining security. Here are some recommended steps.

Immediate Steps to Take

Update e2guardian to a patched version that includes SSL certificate validation.
Disable SSL MITM engine if not essential for operations.
Monitor network traffic for any suspicious activity indicative of MITM attacks.

Long-Term Security Practices

Implement endpoint encryption to secure data transmission.
Regularly review security configurations and protocols to identify vulnerabilities.

Patching and Updates

Stay informed about security advisories and updates related to e2guardian.
Apply patches promptly to mitigate known vulnerabilities and enhance system security.