Constant-Time Equality Check In ColdFusion

This article discusses the concept of timing attacks on string comparison operations and how to mitigate them in ColdFusion. It explains how short-circuiting equality checks can leak information through HTTP response times, allowing attackers to guess secret values character by character. The author provides a ColdFusion function, constantTimeEquals(), that uses bitwise operations to compare strings byte-by-byte without short-circuiting, ensuring constant execution time regardless of where mismatches occur. This technique is applied to Basic Authentication checks to make CFML code more robust against timing attacks.