Preventing Regular Expression Denial of Service (ReDoS) Attacks

Regular expressions are incredibly powerful, but poorly written regex patterns can cause exponential backtracking, leading to a Regular Expression Denial of Service (ReDoS) attack.

What is Exponential Backtracking?

When a regex engine tries to match a string and encounters overlapping groups or nested quantifiers, it may evaluate a huge number of combinations. For example, evaluating (a+)+ against aaaaaaaab requires exponentially more operations for every 'a' added.

Using our local Regex Tester, you can safely test matching paths and discover computational limits without crashing your production process thread.