CVE-2019-11236 Explained : Impact and Mitigation

This CVE record pertains to a CRLF injection vulnerability in the Python urllib3 library up to version 1.24.1, where an attacker can manipulate the request parameter.

Understanding CVE-2019-11236

What is CVE-2019-11236?

CRLF injection can occur in the Python urllib3 library up to version 1.24.1 when the request parameter is controlled by an attacker.

The Impact of CVE-2019-11236

This vulnerability allows attackers to inject CRLF sequences into HTTP headers, potentially leading to various attacks such as HTTP response splitting.

Technical Details of CVE-2019-11236

Vulnerability Description

The vulnerability exists in the Python urllib3 library up to version 1.24.1, enabling CRLF injection when an attacker controls the request parameter.

Affected Systems and Versions

Vendor: n/a
Product: n/a
Versions Affected: up to 1.24.1

Exploitation Mechanism

Attackers can exploit this vulnerability by manipulating the request parameter to inject CRLF sequences into HTTP headers.

Mitigation and Prevention

Immediate Steps to Take

Update the Python urllib3 library to version 1.24.2 or later to mitigate the CRLF injection vulnerability.
Monitor network traffic for any signs of CRLF injection attempts.

Long-Term Security Practices

Regularly update libraries and dependencies to patch known vulnerabilities.
Implement input validation mechanisms to prevent malicious input manipulation.

Patching and Updates

Ensure all systems using the Python urllib3 library are updated to version 1.24.2 or above to address the CRLF injection vulnerability.