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Cisco Open Sources Quarry to Catch AI Agent Attacks Hidden in Harmless Steps

securityweek.com 2026-10-29 AI agent abuse High

Executive Summary

Cisco open sourced Project Quarry to detect AI agent attacks hidden within sequences of harmless-looking steps. Organizations operating AI agents should care because single-action monitoring may miss multi-step abuse.

What Happened

Cisco open sourced Project Quarry, a rule language for detecting AI agent attacks that only emerge across sequences of benign actions. The post Cisco Open Sources Quarry to Catch AI Agent Attacks Hidden in Harmless Steps appeared first on SecurityWeek .

Affected Products

  • Project Quarry

Vulnerability / Attack Technique

Multi-step AI agent attack using sequences of benign actions

Technical Mechanism

Project Quarry uses a rule language to detect attack patterns that emerge across sequences of AI agent actions. The provided article summary does not describe the rule syntax, telemetry requirements, or specific attack sequences.

AI Security Category

LLM06:2025 Excessive Agency

Part of the AI Agent Excessive Agency topic.

Relevant Frameworks

LLM06:2025 Excessive Agency

RealGround Analysis

AI agent risks can arise from the cumulative effect of actions rather than from one obviously malicious step. Teams should test business logic, authorization boundaries, and monitoring against multi-step workflows that appear benign individually but produce harmful outcomes collectively.

Recommended Controls

  • Audit agent workflows for cumulative risk across multi-step action sequences
  • Define and enforce authorization limits for high-impact agent actions
  • Log and correlate agent actions across sessions and workflows
  • Red-team agents with multi-step scenarios involving individually benign actions
  • Deploy rule-based detection for suspicious action sequences

Related RealGround Service

AI Agent Business Logic Audit · or start with the free AI Agent Security Scanner.

Sources

securityweek.com: https://www.securityweek.com/cisco-open-sources-quarry-to-catch-ai-agent-attacks-hidden-in-harmless-steps/

Summary and analysis written by RealGround from the source above; last updated 2026-10-30.

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