fix: replace Math.random() with crypto.getRandomValues() (WAPI-1127)#73
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chakra-guy merged 1 commit intomainfrom Feb 27, 2026
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fix: replace Math.random() with crypto.getRandomValues() (WAPI-1127)#73chakra-guy merged 1 commit intomainfrom
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adonesky1
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packages/wallet-client/src/handlers/untrusted-connection-handler.test.ts
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Math.random() is not cryptographically secure and should never be used for security-sensitive values like OTP generation. Replace with crypto.getRandomValues() which is available in all target runtimes (Node 20+, modern browsers, React Native).
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Summary
Math.random()withcrypto.getRandomValues()for OTP generation in the untrusted connection handlerglobalThis.cryptois guaranteed available in all target runtimes (Node 20+, all modern browsers, React Native)Background
The Cyfrin audit flagged
Math.random()usage for OTP generation.Math.random()uses a non-cryptographic PRNG and its output is predictable, making OTP values potentially guessable.crypto.getRandomValues()provides cryptographically secure randomness.Since Node 18 support was dropped in #76 (WAPI-1133),
globalThis.cryptois always available and no runtime fallback is needed.Changes
packages/wallet-client/src/handlers/untrusted-connection-handler.ts: OTP generation usesUint32Array+crypto.getRandomValues()packages/wallet-client/src/handlers/untrusted-connection-handler.test.ts: Tests for OTP generationTest plan
yarn buildpassesyarn test:unitpasses (62/62 tests)Math.random()calls remain in source filesNote
Medium Risk
Changes OTP generation in the untrusted handshake flow; while small, it affects a security-sensitive step and could impact runtime compatibility if
cryptois unavailable.Overview
Updates the untrusted connection handshake to generate 6-digit OTPs using
globalThis.crypto.getRandomValues()instead ofMath.random().Adds a changelog entry noting the OTP randomness fix.
Written by Cursor Bugbot for commit 3c1336b. This will update automatically on new commits. Configure here.