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Automatically Detect Weak Passwords from Large Password Lists in Python

This Python script identifies weak passwords from a list by checking length, common patterns, sequential characters, and uniform characters, returning those that fail the security checks.

password security validation

Python

import re

COMMON_PASSWORDS_FILE = "common_passwords.txt"

def is_weak(password):
    # Check length
    if len(password) < 8:
        return True
    # Check for common patterns
    if password.lower() in {"password", "123456", "qwerty", "letmein", "admin", "welcome"}:
        return True
    # Check for sequential c…

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Automatically Detect Weak Passwords from Large Password Lists in Python

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Strings & text — Python code examples

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