Improper Neutralization of Special Elements used in a Command ('Command Injection')
Teleport prior to 8.3.17, 9.x prior to 9.3.13, and 10.x prior to 10.1.2 is vulnerable to Command injection leading to Remote Code Execution. An attacker can craft a malicious ssh-agent installation link by URL encoding a bash escape with carriage return line feed. This URL encoded payload can be used in place of a token and sent to a user in a social engineering attack. This is a fully unauthenticated attack utilizing the trusted teleport server to deliver the payload.
CWE-77 - Command Injection
A command injection attack involves injecting an operating system command through the data input, which gets executed on the host operating system with the privileges of the victimized application. The impact of a command injection attack may range from loss of data confidentiality and integrity to unauthorized remote access to the hosting system. The attack may cause serious data breaches and system takeover.