MCP for agent-to-agent comms may be the riskiest protocol you've never heard of
LOST IN TRANSLATION MCP for agent-to-agent comms may be the riskiest protocol you’ve never heard of Trust gaps in the new protocol spread malicious prompts from one agent to another. In the past five months, Google and four other organizations—with little in common except for their use of AI agents—have acknowledged vulnerabilities that exploit one agent inside a targeted network to spread harmful instructions to other internal agents. The technique is a special form of prompt injection that targets not the LLM but a particular agent, such as one for translation or data analysis.
- ▪LOST IN TRANSLATION MCP for agent-to-agent comms may be the riskiest protocol you’ve never heard of Trust gaps in the new protocol spread malicious prompts from one agent to another.
- ▪In the past five months, Google and four other organizations—with little in common except for their use of AI agents—have acknowledged vulnerabilities that exploit one agent inside a targeted network to spread harmful instructions to other
- ▪The technique is a special form of prompt injection that targets not the LLM but a particular agent, such as one for translation or data analysis.
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| Original publisher | Ars Technica |
| Canonical URL | https://arstechnica.com/security/2026/10/vulnerability-in-agents-from-google-and-others-exposes-structural-flaw-in-mcp/ |
| Publication time | Mon, 05 Oct 2026 22:26:35 +0000 |
| Retrieval time | 2026-10-05T22:59:23.442Z |
| Last seen | 2026-10-05T22:59:23.442Z |
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| Cluster | Cw8wfGEeX4i0 · 1 stories |
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Opening excerpt (first ~120 words) tap to expand
LOST IN TRANSLATION MCP for agent-to-agent comms may be the riskiest protocol you’ve never heard of Trust gaps in the new protocol spread malicious prompts from one agent to another. Dan Goodin – Oct 5, 2026 6:26 pm | 7 Credit: Getty Images Credit: Getty Images Text settings Story text Size Small Standard Large Width * Standard Wide Links Standard Orange * Subscribers only Learn more Minimize to nav The adoption of AI agents in millions of organizations is creating new opportunities for attackers to make them take malicious actions, such as exfiltrating database contents and sensitive business and personal information.
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Excerpt limited to ~120 words for fair-use compliance. The full article is at Ars Technica.
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