Misbehavior1 sourceFirst seen
Claude Code Gets Hijacked, Mails Your .env Out Via DNS Ping Requests
Ourtake
The allowlist said ping was harmless. Nobody asked the DNS server what it thought of the secrets arriving.
What happened
Security researcher Johannes Rehberger disclosed a prompt-injection flaw in Anthropic's Claude Code that let injected text in a file trigger allowlisted commands such as ping to leak .env secrets to an external server via DNS queries. Anthropic triaged it as CVSS 7.1 and reported it fixed on June 6, 2025, under CVE-2025-55284.