Agency sharpens one old threat — and adds a new one
Give an AI a tool that fetches any page, and it now chooses the URLs. That
amplifies an old vuln and surfaces a new one:
Old vuln, now automated — SSRF (OWASP Web A10). A hijacked link can steer an
autonomous fetch at your internal network. So before any fetch the server
rejects private/reserved IPs and cloud-metadata hosts, connects only to the
exact resolved address (DNS-rebind defense), and re-checks on every redirect.
A genuinely new class — indirect prompt injection. A booby-trapped page can
try to hijack the AI reading it. The server strips active markup, caps size, and
stamps every result that carries external text with an untrusted-external-content
marker — in the JSON envelope, never inside the content where a page could forge
it, and enforced by a cross-tool drift test so a new tool can't ship unmarked.
It does not enforce the prompt boundary — that's the host's job, where the
model and agent loop live.
Prompt injection is #1 on OWASP's LLM list, and the agentic rules are still
being drafted. This tool sits squarely in that gap.