Incorrect authorization in the certificate-name matching of trapperkeeper-authorization, as used by Puppet Server, in the affected products, allows a client that holds a CA-signed certificate whose name extends or shortens an authorized hostname to be authorized as that host. This enables impersonation of other nodes and, in Puppet Enterprise, access to certificate-authority administration and remote command execution on managed nodes. Exploitation requires a certificate with a colliding name, which the certificate authority issues by approval or autosign.
Upgrade to Puppet Enterprise 2023.8.13, 2025.12.1, or 2026.0.1 as applicable. The fix ships to every service that uses the library.