Issue #3 Protocol Signal June 11, 2026 · Monday

MCP Security Reckoning

MCP's security model came under formal scrutiny as x402 crossed 100 million payments processed and the first dedicated settlement infrastructure for agent payments launched.

MCP tool poisoningprompt injectionx402 milestonessettlement infrastructure

Security researchers published coordinated findings on MCP tool poisoning and cross-server prompt injection, prompting the Anthropic MCP team to accelerate the security working group timeline. Simultaneously, x402 crossed 100 million cumulative payments on Base, and two infrastructure providers launched dedicated settlement rails for agent-to-agent transactions.

Read the full issue

Complete coverage including briefs and source links on Beehiiv.

Read Issue #3
← All issues Subscribe for new issues →