AI agent incident
A flaw reported as PromptFiction, since fixed, let one AI agent automatically send malicious prompts to other agents through the channel they use to talk to each other.
Messages between agents tend to be treated as trusted because they come from inside the system. This shows that channel carries injection the same way any untrusted input does.
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Prompt injection The glossary definition, in plain English.
“A Claude flaw let one agent send malicious prompts to other agents.” The Permission Layer AI Agent Incident Database, https://thepermissionlayer.com/incidents/claude-promptfiction-inter-agent/. Database updated October 22, 2026.
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