Introduction

Security risks in AI applications are not one-size-fits-all. A system processing sensitive customer data presents vastly different security challenges compared to one that aggregates internet data for market analysis. To effectively safeguard an AI application, developers and security professionals must implement comprehensive mechanisms that instruct models to decline contextually malicious requests—such as revealing personally identifiable information (PII) or ingesting data from untrusted sources. Monitoring these refusals provides an early and high-accuracy warning system for potential malicious behavior.

However, current guardrails provided by large language model (LLM) vendors fail to capture the unique risk profiles of different applications. HiddenLayer Refusal Detection, a new feature within the AI Sec Platform, is a specialized language model designed to alert and block users when AI models refuse a request, empowering businesses to define and enforce application-specific security measures.

Addressing the Gaps in AI Security

Today’s generic guardrails focus on broad-spectrum risks, such as detecting toxicity or preventing extreme-edge threats like bomb-making instructions. While these measures serve a purpose, they do not adequately address the nuanced security concerns of enterprise AI applications. Defining malicious behavior in AI security is not always straightforward—a request to retrieve a credit card number, for example, cannot be inherently categorized as malicious without considering the application’s intent, the requester’s authentication status, and the card’s ownership.

Without customizable security layers, businesses are forced to take an overly cautious approach, restricting use cases that could otherwise be securely enabled. Traditional business logic rules, such as allowing customers to retrieve their own stored credit card information while blocking unauthorized access, struggle to encapsulate the full scope of nuanced security concerns.

Generative AI models excel at interpreting nuanced security instructions. Organizations can significantly enhance their AI security posture by embedding clear directives regarding acceptable and malicious use cases. While adversarial techniques like prompt injections can still attempt to circumvent protections, monitoring when an AI model refuses a request serves as a strong signal of potential malicious activity.

Introducing HiddenLayer Refusal Detection

HiddenLayer’s Refusal Detection leverages advanced language models to track and analyze refusals, whether they originate from upstream LLM guardrails or custom security configurations. Unlike traditional solutions, which rely on limited API-based flagging, HiddenLayer’s technology offers comprehensive monitoring capabilities across various AI models.

Key Features of HiddenLayer Refusal Detection:

  • Universal Model Compatibility – Works with any AI model, not just specific vendor ecosystems.
  • Multilingual Support – Provides basic non-English coverage to extend security reach globally.
  • SOC Integration – Enables security operations teams to receive real-time alerts on refusals, enhancing visibility into potential threats.

By identifying refusal patterns, security teams can gain crucial insights into attacker methodologies, allowing them to strengthen AI security defenses proactively.

Empowering Enterprises with Seamless Implementation

Refusal Detection is included as a core feature in HiddenLayer’s AIDR, allowing security teams to activate it with minimal effort. Organizations can begin monitoring AI outputs for refusals using a more powerful detection framework by simply setting the relevant flag within their AI system.

Get Started with HiddenLayer’s Refusal Detection

To leverage this advanced security feature, update to the latest version of AIDR. Refusal detection is enabled by default with a configuration flag set at instantiation. Comprehensive deployment guidance is available in our online documentation portal.

By proactively monitoring AI refusals, enterprises can reinforce their AI security posture, mitigate risks, and stay ahead of emerging threats in an increasingly AI-driven world.