Campus administrators must update systems using Duo software, SDKs, and APIs before Feb. 2, 2026, to prevent service disruptions.
What’s happening
Duo is updating its Certificate Authority (CA) bundle and the existing one will expire in early 2026. Systems and applications using outdated versions of Duo software for multifactor authentication will lose their connection to Duo’s service after this change is complete.
Important deadlines
- Feb. 2, 2026: Perform updates by this date to avoid access issues.
- March 31, 2026: Outdated software will fail after this final deadline.
Next steps
To ensure a smooth transition, please follow these steps to update your systems as soon as possible:
- Review the FAQs: Read University IT’s Duo Certificate Expiration FAQs for Stanford-specific guidance and best practices.
- Check versions: Use Duo’s help article to find minimum software versions available for your applications and check your current software versions.
What else?
If you are a Linux and Windows server admins, you should update the Duo software on your systems to ensure functionality.
- For Linux and Unix systems: The Information Security Office recommends using the latest version available from official Duo software repositories.
- For Windows systems: Download the latest software from the Duo website.
Additionally, if you are a developer, review the versions deployed in your project to check for compatibility with the latest updates.
What about end users?
Typically, no action is required. The Duo Mobile app should update automatically on supported mobile OS versions.
Get help
If you need assistance or have questions, please submit a Help request.
