CVE-2017-5868 : Security Advisory and Response

OpenVPN Access Server 2.1.4 is susceptible to a CRLF injection vulnerability that allows attackers to inject unauthorized HTTP headers, potentially leading to session fixation and HTTP response splitting attacks.

Understanding CVE-2017-5868

This CVE involves a security vulnerability in the web interface of OpenVPN Access Server 2.1.4.

What is CVE-2017-5868?

The presence of a CRLF injection vulnerability in OpenVPN Access Server 2.1.4 allows attackers to inject unauthorized HTTP headers, leading to session fixation and potential HTTP response splitting attacks.

The Impact of CVE-2017-5868

Attackers can inject unauthorized HTTP headers through the web interface of OpenVPN Access Server 2.1.4.
This injection can result in session fixation attacks and potentially enable HTTP response splitting attacks.

Technical Details of CVE-2017-5868

OpenVPN Access Server 2.1.4 is affected by a CRLF injection vulnerability.

Vulnerability Description

The vulnerability enables remote attackers to inject arbitrary HTTP headers by including "%0A" characters in the PATH_INFO to session_start/.

Affected Systems and Versions

Product: OpenVPN Access Server 2.1.4
Vendor: N/A
Version: N/A

Exploitation Mechanism

The vulnerability can be triggered by injecting "%0A" characters in the PATH_INFO to session_start/.

Mitigation and Prevention

It is crucial to take immediate steps to address and prevent exploitation of CVE-2017-5868.

Immediate Steps to Take

Update OpenVPN Access Server to a patched version that addresses the CRLF injection vulnerability.
Monitor and restrict input that could potentially contain malicious characters.

Long-Term Security Practices

Regularly update and patch software to mitigate known vulnerabilities.
Implement secure coding practices to prevent injection attacks.

Patching and Updates

Apply security patches provided by OpenVPN to fix the CRLF injection vulnerability in Access Server 2.1.4.