Best Practices for Secure Printing Using the Terminal Server Printer Redirection WizardSecure printing in remote desktop and terminal server environments is a mix of correct configuration, careful network design, and disciplined operational practices. The Terminal Server Printer Redirection Wizard (hereafter “the Wizard”) simplifies connecting client printers to remote sessions, but if left with default settings or without attention to security controls, it can expose sensitive data, widen the attack surface, or cause operational problems. This article covers best practices for planning, configuring, and operating secure printing with the Wizard, including authentication, driver management, encryption, logging, and troubleshooting.
Executive summary
- Understand the feature: The Wizard redirects client-side printers into remote sessions so users can print from applications running on a terminal server to their local printers.
- Major risks: unauthorized data exposure, driver-based vulnerabilities, credential theft via misconfiguration, and Denial of Service from malformed print jobs or rogue drivers.
- Goal: allow expected printer functionality while minimizing privileged access, surface area, and data leakage.
1. Planning and requirements
Start with a clear inventory and policy. Know what printing scenarios you must support (local USB printers, network printers on client LANs, virtual PDF printers, print servers), what data sensitivity levels exist, and which users need redirection.
- Maintain an inventory of supported client printer types and driver families.
- Define acceptable printers/drivers in an allowlist. Block unknown/unsupported drivers.
- Decide where print rendering should occur: on the client, on the server, or on a dedicated print server. Rendering on the client reduces server load and exposure; rendering on a trusted print server centralizes control.
Security policy considerations:
- Limit which users/groups can use redirection.
- Determine retention and handling of spool files or temporary PDFs created during print redirection.
- Ensure compliance with data protection rules (e.g., GDPR, HIPAA) when printouts contain sensitive information.
2. Authentication and access control
- Enforce strong authentication for terminal server access (MFA, smart cards, or certificate-based authentication). This prevents unauthorized sessions that could abuse redirected printers.
- Use least privilege: only give users the permissions they need to access redirected printers; restrict administrative rights on terminal servers.
- If using service accounts for printing tasks, manage and rotate credentials securely.
3. Configure the Terminal Server Printer Redirection Wizard securely
- Use Group Policy (or equivalent management tools) to control Wizard behavior across the environment. Key settings:
- Disable automatic installation of client printer drivers unless they are on the allowlist.
- Configure “Do not allow client printer redirection” for groups that shouldn’t use the feature.
- Set policies to redirect only default client printers, or disable redirection of client printers entirely if unnecessary.
- If the Wizard offers options to select rendering location, prefer client-side rendering when acceptable.
- Disable legacy protocols and insecure options within the Wizard or related RDP settings.
Example Group Policy paths (Windows Server environments):
- Computer Configuration → Administrative Templates → Windows Components → Remote Desktop Services → Remote Desktop Session Host → Printer Redirection
- Enable “Use Remote Desktop Easy Print printer driver first” to reduce third-party driver exposure (see Driver Management).
4. Driver management and Easy Print
Printer drivers are a common attack vector. Follow these practices:
- Prefer Microsoft Remote Desktop Easy Print driver when possible. Easy Print minimizes server-side driver installs by using a generic driver on the server and the client’s drivers for rendering.
- Maintain a central, signed, allowlisted set of printer drivers for any drivers that must be installed on servers. Block installation of unsigned or unapproved drivers through Group Policy.
- Keep all printer drivers and print-related software up to date with vendor patches.
- Test any new driver in a staging environment for compatibility and security before deploying.
Driver deployment options:
- Preinstall common drivers on a gold image for terminal servers.
- Use driver isolation (Windows Print Spooler driver isolation) to reduce impact of faulty drivers.
5. Network and transport security
- Always use encrypted remote sessions (RDP over TLS) and enforce NLA (Network Level Authentication).
- Protect print server communications with IPsec or TLS where possible, especially when print jobs traverse untrusted networks.
- If printing to network printers on the client LAN, ensure those printers support secure management (HTTPS, SNMPv3) and apply strong admin credentials.
6. Spooling, data handling, and privacy
Spool files created during redirection can contain sensitive data. Protect them:
- Configure secure spooler settings and ensure temporary spool files are written to encrypted storage when containing sensitive data.
- Implement automatic secure deletion of temporary print files after job completion.
- Limit which users can access spooler files and monitor for unusual access patterns.
Consider using pull printing or secure release stations for high-sensitivity environments: users authenticate at a release station before their print job is released, preventing unattended documents.
7. Logging, monitoring, and alerting
Visibility is essential to detect misuse:
- Enable and centralize logging for print-related events (job submissions, failures, spooler errors, driver installs).
- Monitor for abnormal patterns: spikes in print volume, repeated driver failures, or frequent job cancellations.
- Alert on suspicious events such as installs of unapproved drivers, repeated authentication failures, or print jobs originating from unexpected endpoints.
Integrate logs with SIEM for correlation with other security events.
8. Hardening the print environment
- Minimize installed print features and third-party components on terminal servers. Remove unused printer drivers and services.
- Harden the print spooler service: apply vendor and Microsoft hardening guidance (e.g., limit privileges, disable routing and remote administration if not needed).
- Use Windows features like Print Spooler service isolation and constrain service accounts.
9. Operational procedures and user training
- Create step-by-step user guides for adding and using redirected printers securely. Educate users about risks of printing sensitive information on shared or public printers.
- Train helpdesk staff on secure driver deployment, how to use the Wizard safely, and how to respond to print-related incidents.
- Run regular audits of printer allowlists, driver inventories, and Group Policy settings.
10. Troubleshooting common issues securely
Common problems and secure fixes:
- Printer not redirected: verify Group Policy settings, client RDP client options, and server-side redirection policies. Avoid temporary enabling of insecure settings; instead, use allowlists and test changes in staged environments.
- Driver mismatch errors: use Easy Print or preinstall matching drivers on server images.
- Slow printing or large spool files: consider client-side rendering or compression where possible.
When troubleshooting, avoid leaving debugging settings enabled in production (e.g., verbose logging) longer than necessary.
11. Advanced options and architectures
- Consider using a centralized print server that receives redirected print jobs and applies consistent security controls, auditing, and driver management. This can centralize risk but also create a single point to harden.
- For high-sensitivity environments, use virtual channels with restricted permissions or custom print redirection solutions that enforce stronger access controls and encryption.
- Evaluate third-party secure printing solutions that integrate with RDS/Citrix environments for features like secure release, watermarking, or content inspection.
12. Checklist — Quick implementation steps
- Inventory printers and classify sensitivity.
- Enable NLA and TLS for RDP sessions.
- Use Easy Print and allowlist drivers; disable automatic unsigned driver installs.
- Restrict printer redirection via Group Policy to necessary users/groups.
- Harden print spooler and enable driver isolation.
- Encrypt spool storage and enable secure deletion.
- Centralize logging and set alerts for abnormal print events.
- Train users and IT staff; test changes in staging first.
Conclusion
The Terminal Server Printer Redirection Wizard is a convenient feature that, when configured with security in mind, lets users retain familiar printing workflows without exposing the terminal environment to unnecessary risks. Prioritize driver management (use Easy Print), enforce strong authentication and encrypted sessions, limit redirection through policy, and maintain logging and operational discipline. With these practices you can significantly reduce the attack surface while delivering reliable printing to remote users.
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