CVE-2018-14774 : Exploit Details and Defense Strategies

A vulnerability has been discovered in the HttpKernel component of Symfony versions 2.7.0 through 2.7.48, 2.8.0 through 2.8.43, 3.3.0 through 3.3.17, 3.4.0 through 3.4.13, 4.0.0 through 4.0.13, and 4.1.0 through 4.1.2. When utilizing HttpCache, the X-Forwarded-Host headers are mistakenly considered as trusted, when they should be prohibited. This could potentially result in host header injection.

Understanding CVE-2018-14774

This CVE identifies a vulnerability in Symfony's HttpKernel component that could lead to host header injection when using HttpCache.

What is CVE-2018-14774?

This CVE refers to a security issue in Symfony versions 2.7.0 through 2.7.48, 2.8.0 through 2.8.43, 3.3.0 through 3.3.17, 3.4.0 through 3.4.13, 4.0.0 through 4.0.13, and 4.1.0 through 4.1.2, where X-Forwarded-Host headers are incorrectly trusted, potentially allowing for host header injection.

The Impact of CVE-2018-14774

The vulnerability could be exploited to inject malicious host headers, leading to various security risks such as spoofing attacks and unauthorized access.

Technical Details of CVE-2018-14774

This section provides more technical insights into the CVE.

Vulnerability Description

The issue arises from the incorrect trust of X-Forwarded-Host headers in Symfony's HttpKernel component, enabling potential host header injection attacks.

Affected Systems and Versions

Symfony versions 2.7.0 to 2.7.48
Symfony versions 2.8.0 to 2.8.43
Symfony versions 3.3.0 to 3.3.17
Symfony versions 3.4.0 to 3.4.13
Symfony versions 4.0.0 to 4.0.13
Symfony versions 4.1.0 to 4.1.2

Exploitation Mechanism

The vulnerability occurs when HttpCache mistakenly treats X-Forwarded-Host headers as trusted, allowing attackers to manipulate host headers and potentially perform malicious actions.

Mitigation and Prevention

To address CVE-2018-14774, follow these mitigation strategies:

Immediate Steps to Take

Update Symfony to the patched versions that address the vulnerability.
Disable HttpCache if not essential to mitigate the risk of host header injection.

Long-Term Security Practices

Regularly monitor and apply security updates for Symfony and its components.
Implement strict input validation and sanitization to prevent header injection attacks.

Patching and Updates

Apply the official patches provided by Symfony to fix the vulnerability and enhance system security.