Breaking Through the Firewall: How I Bypassed a WAF and Found a Critical Bug with $1700
1 min read
Summary
A hacker has explained how they overcame a Web Application Firewall (WAF) which had blocked all attempts to find vulnerabilities in a target system.
After hours of attempting conventional types of attack, the hacker decided to think outside the box, recalling the adage that every security system has a weakness.
A WAF is designed to filter out bad traffic, and as a result, is constantly processing a high level of data, which can mean that it is also a potential bottleneck in terms of performance.
The hacker used this knowledge to craft a specific type of attack which targeted the WAF’s filtering process itself, draining the daemon’s resources, and causing an internal server error.
This error revealed a previously unseen error message, which contained a SQL injection vulnerability.
From there, the hacker was able to gain further access, and found a critical bug with a cash bounty of $1,700.