Description

This detector identifies vulnerable usage of Go's scrypt library with weak key derivation parameters. Scrypt is a password-based key derivation function where insufficient CPU/memory cost parameters make passwords vulnerable to brute-force attacks.

Detection Strategy

• Scans Go source code files that import the golang.org/x/crypto/scrypt library or use a scrypt alias

• Skips test files to avoid flagging legitimate weak parameters used in testing scenarios

• Analyzes function calls to scrypt methods and evaluates the cost parameters (N, r, p values)

• Reports violations when scrypt is called with parameters that fall below secure thresholds for computational cost and memory usage

• Triggers when the combination of CPU cost (N), block size (r), and parallelization (p) parameters are insufficient to resist modern brute-force attacks

Vulnerable code example

package main

import "golang.org/x/crypto/scrypt"

func deriveKeyWeak(password string, salt []byte) ([]byte, error) {
	return scrypt.Key([]byte(password), salt, 1024, 8, 1, 32) // Weak N parameter < 32768
}
...

✅ Secure code example

package main

import "golang.org/x/crypto/scrypt"

func deriveKeyWeak(password string, salt []byte) ([]byte, error) {
	return scrypt.Key([]byte(password), salt, 32768, 8, 1, 32) // N >= 32768 for secure scrypt
}
...