The internet runs on HTTP (Hypertext Transfer Protocol), which is responsible for transferring data between a web server and a browser. To maintain a secure communication environment, parsing the HTTP protocol is crucial in detecting malicious activities. LibHTP is widely used for this purpose as a security-aware HTTP parser that goes beyond the functionality of a generic parser.
Recently, an exploitable vulnerability has been discovered in LibHTP, assigned as CVE-2024-23837. This vulnerability allows a potential attacker to cause an excessive processing time of HTTP headers resulting in a denial of service (DoS). This blog post will provide detailed information on the exploit, code snippet, and the fix to address this issue in the LibHTP version .5.46.
Exploit Details
A specifically crafted HTTP request can trigger this vulnerability, causing LibHTP to spend an excessive amount of time processing HTTP headers. As a result, the targeted application can suffer performance bottlenecks, resulting in a temporary unavailability or denial of service.
The exploit leverages the HTTP headers with a large number of field values, as illustrated in this code snippet:
GET / HTTP/1.1
Host: www.example.com
User-Agent: [Repeated 100000 times]
Connection: keep-alive
This carefully crafted request could be sent multiple times to overwhelm the target server, causing a denial of service.
Further details on this vulnerability can be found in the CVE database
The official LibHTP GitHub repository will also provide additional information
The Fixed Version - LibHTP .5.46
To mitigate this vulnerability, the developers have released a patch in the LibHTP version .5.46, which incorporates a mechanism to limit the processing time while parsing HTTP headers.
You can download and install the latest patched version from the GitHub repository
Or you can update your dependency through package managers such as apt, yum or pip
# Debian-based systems
apt update
apt upgrade libhtp
# Red Hat-based systems
yum update libhtp
# Python
pip install --upgrade libhtp
Recommendations
It is highly advised to upgrade to the latest LibHTP .5.46 version as soon as possible to prevent any possible exploits leveraging the CVE-2024-23837 vulnerability. Moreover, ensure that your security controls are up-to-date and apply appropriate monitoring measures to detect any anomalies in traffic patterns.
To extend the effectiveness of LibHTP as a security-aware HTTP parser, it can be combined with other security solutions such as intrusion prevention systems, web application firewalls, or comprehensive security monitoring tools.
Summary
The CVE-2024-23837 vulnerability in LibHTP can lead to a potential denial of service by causing excessive processing time for HTTP headers. To mitigate this issue, upgrade to the LibHTP .5.46 version and implement security measures, ensuring a secure and resilient internet environment.
Timeline
Published on: 02/26/2024 16:27:57 UTC
Last modified on: 03/07/2024 03:15:07 UTC