Cline Bot AI Coding Agent Data Exfiltration via Prompt Injection and DNS

Affected Vendor(s)

Affected Product(s)

Summary

Through malicious instructions planted in a source code file, Cline can be coerced into exfiltrating sensitive key material from a user’s environment to an attacker-controlled location.

Cline is vulnerable to prompt injection when analyzing source code files. Furthermore, this prompt injection can be used to execute what is considered a safe command (ping), which requires no user approval, in a way that will exfiltrate sensitive key material to an attacker-controlled location.

Timeline

Discovered on
August 24, 2025
Disclosed to Vendor on
August 27, 2025
Published on
November 18, 2025

Credit

Blog Post

References