The tri-agency advisory AA26-251A, jointly published by the NSA, CISA, and the FBI, details industrial-scale knowledge distillation campaigns that route requests through native APIs, cloud providers, third-party aggregators, and a gray market of proxy relays. For organizations operating model-serving infrastructure, the critical question is visibility: which systems fronting frontier-model APIs are visible from the outside, and can they be identified reliably?

The 'Transfer Station' Threat Vector

The advisory explicitly categorizes third-party aggregators and proxy relays as "transfer stations." These systems act as intermediaries, allowing actors to mask the origin of distillation queries while leveraging the computational power of upstream models. The advisory attributes billions of extracted tokens to campaigns that routed requests through multiple pathways. A gateway that proxies requests to several upstream models becomes a natural chokepoint in this picture. Identifying these systems on your own network range, before an adversary maps them via external scanning, is described as a defensible first step in mitigating unauthorized token extraction.

Leveraging Asset Search Engines for Visibility

To operationalize this visibility, the report highlights the utility of asset search engines like ZoomEye, operated by Knownsec. These tools index HTTP responses and banners, allowing security teams to query for specific software signatures. For instance, using syntax such as title="new-api" can reveal panels that identify themselves through the New API gateway project. This method moves beyond theoretical risk assessment, providing concrete data on which gateway software is exposed to the public internet and potentially serving as a vector for the campaigns described in AA26-251A.

Mandatory Actions and Critical Limitations

The authoring agencies recommend three immediate actions: implement comprehensive detection and mitigation strategies, deploy targeted response changes, and establish cross-organization intelligence sharing. However, a crucial caveat accompanies these directives. A panel title appearing in a search engine result is evidence of software presence, not proof of active misuse or compromise. Exposure counts reflect matching assets, not confirmed abuse. Attribution claims within the advisory remain subject to the inherent caveats of remote fingerprinting, meaning organizations must distinguish between vulnerable architecture and active exploitation.

Key Takeaways

  • Advisory AA26-251A identifies proxy relays and aggregators as key vectors for industrial-scale LLM distillation.
  • Asset search engines like ZoomEye enable the identification of exposed gateways (e.g., New API) via banner indexing.
  • CISA, NSA, and FBI mandate detection, response changes, and intelligence sharing for organizations serving AI models.
  • Exposure counts are not equivalent to compromise; distinct verification is required to confirm actual misuse.

The Bottom Line

Visibility is the new perimeter; if you aren't actively mapping your exposed LLM gateways, you are leaving billions of tokens vulnerable to silent extraction.