The ApplicationName and LogoURL appearance settings were rendered into HTML output without sufficient escaping which let a highly privileged Owner-role user inject HTML into the Coder dashboard and SMTP notification emails.

An Owner-role user could store HTML markup in the ApplicationName or LogoURL appearance settings that later rendered in the dashboard and in SMTP notification emails which results in stored HTML injection against other users of the deployment. Exploitation requires the highly privileged Owner role.

The fix escapes the ApplicationName and LogoURL appearance values in HTML output before rendering.

The fix was backported to all supported release lines:

Restrict the Owner role to trusted administrators.

We'd like to thank Anthropic's Security Team (ANT-2026-22453) for independently disclosing this issue!