From 0 to $$$: Finding Rate Limit Bypasses Like a Pro
1 min read
Summary
This article offers a comprehensive guide to identifying and exploiting rate limit bugs, which are vulnerabilities in applications that allow attackers to bypass rate limits and submit an unlimited number of requests to a target endpoint.
The authors describe rate limit bypass as a security vulnerability that arises when an attacker finds a way to send a high volume of requests to a specific endpoint without triggering any blocks or delays.
The article highlights several common areas where rate limiting is typically applied, such as authentication flows, account recovery/password reset processes, and other functionalities.
It also discusses several techniques that can be used to bypass rate limits, including rotating IP addresses, using multiple IP headers, leveraging TOR or proxies, rotating user-agent and other headers, and employing delay-based evasion.
The article then provides a step-by-step methodology for identifying rate limit bypass vulnerabilities, including finding a target function, sending multiple requests quickly, and analyzing the server’s response to determine if a rate limit bypass is present.