R01 Weak Randomness

What this means

SiteShadow flagged use of non-cryptographic randomness for security-sensitive values (tokens, reset links, session IDs, invitation codes, API keys, nonce/IV generation).

Why it matters

Predictable randomness can enable guessing attacks and token compromise.

• Account takeover: attackers can guess password reset or invite tokens.
• Session hijacking: predictable session IDs are catastrophic.
• Crypto failures: weak nonces/IVs can break encryption guarantees.

Safer examples

1) Use a cryptographically secure RNG

import { randomBytes } from "node:crypto";
const token = randomBytes(32).toString("hex");

import secrets
token = secrets.token_urlsafe(32)

2) Don't use Math.random() / random() for secrets

Those are fine for UI effects and simulations, not auth tokens.

3) Keep token length sufficient

Use at least 128 bits of entropy for security tokens (often 16+ bytes).

How SiteShadow detects it (high level)

• Detects calls to non-crypto RNG APIs near security-sensitive variable names/uses.
• Flags "random token" construction patterns that don't use secure RNGs.

References

• CWE-338: https://cwe.mitre.org/data/definitions/338.html

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