Resafe / Docs
Hello
Welcome to Resafe - intelligent ReDoS detection for your regex patterns.
What is ReDoS?
Regular Expression Denial of Service occurs when a regex engine gets stuck in catastrophic backtracking, potentially freezing your application's event loop. A single malicious input can bring down your entire service.
// This innocent-looking regex can freeze your app
const dangerous = /(a+)+$/;
dangerous.test("aaaaaaaaaaaaaaaaaaaaX"); // Takes exponential time!How Resafe Helps
Resafe analyzes regex patterns before execution using mathematical spectral analysis:
- Prevention First: Block unsafe patterns before they reach production
- Spectral Analysis: Thompson NFA construction with eigenvalue computation
- Fast Analysis: Average analysis time <1ms per typical pattern
- Deterministic: Analyzes automaton structure, not heuristic patterns