Custom Password Blacklist

CheckID supports custom password blacklists, allowing organisations to prevent the use of weak, predictable, or organisation-specific passwords during password creation or reset.

This capability aligns with modern identity security practices and complements global banned password controls.

How It Works

When enabled, CheckID validates new or changed passwords against:

• The global banned password list
• The organisation’s custom banned password list (if configured)

If a password matches a banned term, the password is rejected and the user must choose a different password.

Normalisation and Matching Logic

To prevent simple bypass techniques, CheckID applies password normalisation before validation. This includes:

• Converting the password to lowercase
• Applying common character substitutions (e.g. @ → a, $ → s, 0 → o)

This ensures that trivial variations are detected when the base term (e.g. password) is banned:

• Password1
• P@ssw0rd
• Pa$$word
• passw0rd123

Configuration and Submission of List

List Creation

To configure a custom banned password list:

1. The customer prepares a plain text file containing banned terms
2. One term per line

File Format Requirements

• File type: .txt
• Encoding: UTF-8
• One term per line
• No special formatting
• Maximum size: defined per contract or environment limits

Example File

checkid
companyname
helsinki
internaltool
projectx

Submission of List

1. The file is sent securely to the CheckID team
2. The list is imported into the customer’s CheckID instance
3. Confirmation is provided once activation is complete

Important Notes