How Two Small Bugs Led to a Critical Vulnerability and a Cryptography Audit of Go's SSH Library
Last summer we found a critical vulnerability in Teleport, our first in a decade. It was assigned CVE-2025-49825. This vulnerability allowed Teleport SSH certificates, issued to users of a cluster, to sign other SSH certificates which would then be incorrectly accepted by Teleport as valid. Once you can sign your own certificates, you can escalate privileges and bypass authentication controls. This is why we classified it as a critical vulnerability.