CVE-2019-19886 Explained : Impact and Mitigation

Trustwave ModSecurity versions 3.0.0 to 3.0.3 contain a vulnerability that allows attackers to slow down or render a server unresponsive by sending specially crafted requests at high volumes.

Understanding CVE-2019-19886

This CVE identifies a flaw in Trustwave ModSecurity versions 3.0.0 to 3.0.3 that can lead to a Denial of Service (DoS) attack.

What is CVE-2019-19886?

Trustwave ModSecurity 3.0.0 through 3.0.3 is susceptible to a DoS attack where an attacker can exploit a flaw in the Transaction::addRequestHeader function in transaction.cc by inundating the server with crafted requests.

The Impact of CVE-2019-19886

The vulnerability can result in a server becoming slow or unresponsive due to the excessive volume of malicious requests.

Technical Details of CVE-2019-19886

Trustwave ModSecurity versions 3.0.0 to 3.0.3 are affected by this vulnerability.

Vulnerability Description

The flaw in the Transaction::addRequestHeader function in transaction.cc allows attackers to exploit the server by sending a large number of specially crafted requests.

Affected Systems and Versions

Trustwave ModSecurity versions 3.0.0 to 3.0.3

Exploitation Mechanism

Attackers can exploit this vulnerability by sending a high volume of specially crafted requests, causing the server to slow down or become unresponsive.

Mitigation and Prevention

To address CVE-2019-19886, follow these steps:

Immediate Steps to Take

Update Trustwave ModSecurity to a non-vulnerable version.
Implement rate limiting to mitigate the impact of DoS attacks.
Monitor server performance for any signs of unusual activity.

Long-Term Security Practices

Regularly update and patch software to prevent known vulnerabilities.
Conduct security assessments and penetration testing to identify and address weaknesses.

Patching and Updates

Apply patches provided by Trustwave for the affected versions to fix the vulnerability.