PIN Security & Length

Last Updated: July 23, 2026

A personal identification number (PIN) is a numeric code that verifies a user's identity at a device. Choosing a PIN length is a balance between speed and security. Shorter PINs are faster to enter but easier to guess. This topic explains how PIN length affects security, the protections the Control Panel Application (CPA) provides beyond length alone, and how to choose a length for your environment.

Key Points

Review the following key points:

The CPA adds protection beyond PIN length, including physical presence, rate limiting with account lockout, and audit logging.
Vasion recommends a minimum of six digits and shows a warning if you select fewer.
Your physical security controls, document sensitivity, and compliance requirements determine the right length for your environment.

How PIN Length Affects Security

The main threat to a numeric PIN is a brute-force attack, in which an automated tool tries every possible combination in sequence. Each digit you add multiplies the number of combinations by 10, so a longer PIN takes proportionally longer to exhaust. A six-digit PIN has 100 times as many possible combinations as a four-digit PIN, which makes attacks significantly less practical, particularly in environments without hardware lockout mechanisms.

Possible Combinations by PIN Length
PIN Length	Total Combinations
Four digits	10,000
Five digits	100,000
Six digits	1,000,000
Seven digits	10,000,000
Eight digits	100,000,000
Nine digits	1,000,000,000
Ten digits	10,000,000,000

PIN length alone does not guarantee security. Automated attacks typically start with the most common PINs, such as 1234, 0000, and 1111, and predictable sequences, such as 123456 or repeated digits. Avoiding predictable sequences is as important as PIN length, so a randomly assigned PIN is meaningfully more secure than a patterned one of the same length.

How the CPA Reduces Brute-Force Risk

In an offline attack, such as one against a stolen PIN database, an attacker can try combinations rapidly, so length alone offers limited protection. Authentication at a Multifunction Printer (MFP) is different. The CPA includes several protection layers that reduce the practical risk of a brute-force attack, regardless of PIN length:

Physical presence: An attacker must be physically present at the device and cannot attack over the network. The attacker is visible to employees and security cameras and must have building or room access.
Rate limiting and account lockout: The CPA locks an account after a defined number of failed attempts. Manual entry takes about 3 seconds per attempt, so exhausting all 10,000 combinations of a four-digit PIN would take about 8 hours of continuous attempts at the device.
Audit logging: The CPA records authentication attempts in the Printer Apps log. Admins can review the log for failed attempts and suspicious activity. For more details refer to PrinterLogic Log File Locations.

Select a PIN Length for Your Environment

Your physical security controls, document sensitivity, and compliance requirements determine the appropriate PIN length. Use the following table as a starting point.

PIN Length by Environment
Environment	Commonly Selected Length	Factors
Secured facilities with badge access to print rooms	Four to six digits	Physical security controls, rate limiting, and audit logging offset the risk of a shorter PIN.
Mixed security environments	Six to eight digits	A moderate length balances security controls and usability.
Open or public printer locations	Eight to ten digits	Limited physical security increases the need for authentication complexity.

Consider four or five digits if any of the following apply:

Printers are in badge-access secured rooms.
Your building has physical access controls.
Users prioritize authentication speed.
Printed documents are not highly sensitive.
You review audit logs regularly.

Consider six or more digits if any of the following apply:

Printers are in open or public areas.
Your environment has limited or no physical security controls.
Users print sensitive or confidential documents.
Compliance requirements mandate stronger authentication.
Your organization takes a defense-in-depth approach.

Strengthen Security Beyond PIN Length

PIN length is one factor in your overall security strategy. Consider the following measures regardless of the length you select:

Use badge authentication as the primary method and PIN authentication as a backup.
Review audit logs regularly for failed attempts and suspicious patterns.
Train users not to share PINs.
Avoid PINs based on sequences, repeated digits, or personal information, such as birthdates.
Apply physical security controls around high-value printers.
Segment your network to isolate print infrastructure.

Acknowledge Shorter PIN Risk

If you select a PIN length of five or fewer digits in the Admin Console, a security warning appears. By acknowledging the warning and proceeding, your organization confirms the following:

Shorter PINs are more susceptible to guessing attacks than longer PINs.
Your organization accepts this trade-off based on its physical security controls and usability requirements.
Vasion has provided this security guidance.
Your organization is responsible for assessing and accepting the risk.

Start with the default six-digit length, and adjust based on user feedback and security monitoring over time.

Additional Resources

Refer to the following external resources for more information about PIN security standards: