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ATR-2026-00104criticalPrompt Injectionexperimental

Persona Hijacking via Mandatory System Prompt Override

Detects MCP tools that attempt to override system prompts or behavioral guidelines by instructing the AI to "adopt" a persona and "replace" existing instructions. This is a prompt injection attack delivered through tool descriptions rather than user input, exploiting the trust relationship between the LLM and its tools to fundamentally alter the agent's behavior and identity.

Severity
critical
Category
Prompt Injection
Scan Target
mcp
Author
ATR Community

Response Actions

block toolalertsnapshot

References

OWASP Agentic
ASI01:2026 - Agent Goal HijackASI10:2026 - Rogue Agents
OWASP LLM
LLM01:2025 - Prompt InjectionLLM07:2025 - System Prompt Leakage
MITRE ATLAS
AML.T0051 - Prompt Injection