Egress Lock v0.1 — Transitive Egress Closure for AI Cyber Evaluations
桑杰戈 · Team Dawnline
Submitted to AI Incident Response Sprint. Sprint projects are early-stage work by participants, not Apart Research publications.
Egress Lock is a low-cost containment standard for guardrails-off AI cyber evaluations. It addresses a failure mode demonstrated by the July 2026 Hugging Face incident: an evaluated agent may lack direct Internet access yet obtain external connectivity by inducing a reachable intermediary service to relay requests on its behalf.
We define Transitive Egress Closure (TEC): every network-capable service reachable by the evaluated agent must either be unable to relay arbitrary external requests, or have its egress enforced by the same controlled boundary. Our reference harness uses real Linux network namespaces and nftables, a deliberately vulnerable artifact proxy, an independent Canary, and isolated management control.
The final measured run covered 33 atomic test items: 26 PASS, 2 PASS (bounded), and 5 NOT PROVEN. The strongest result is a 6/6 TEC relay test in which the vulnerable proxy could be induced to attempt external access, but the second hop was blocked while a direct positive control remained allowed. The prototype does not claim universal Internet impossibility, real-Internet coverage, or physical-hardware assurance.
Reviews
I think Egress Lock provides a useful demonstration of restricting an agent’s network access. The reported experiment blocks a vulnerable relay under the locked policy and allows it during a temporary exception. The report clearly explains the test and acknowledges that three privilege checks remain unproven.
My next question is whether legitimate evaluations can still run under those restrictions. A successful web request does not establish that dependency downloads work. I would test a realistic package download task alongside the relay attempt, then check whether an agent with its assigned permissions can change the restrictions. That would give teams stronger evidence for deciding whether to adopt the policy.
Cite this project
@misc{apart2026egress,
title = {{Egress Lock v0.1 — Transitive Egress Closure for AI Cyber Evaluations}},
author = {桑杰戈},
year = {2026},
month = sep,
note = {Submitted to AI Incident Response Sprint, an Apart Research Sprint},
howpublished = {\url{https://apartresearch.com/sprints/projects/egress-lock-v01-transitive-egress-closure-for-ai-cyber-evaluations-3f0m}},
url = {https://apartresearch.com/sprints/projects/egress-lock-v01-transitive-egress-closure-for-ai-cyber-evaluations-3f0m}
}More from AI Incident Response Sprint
- View project: Adaptive AI-Based Containment of Autonomous Cyber Attacks: A Reproducible Docker Cyber Range Study
Adaptive AI-Based Containment of Autonomous Cyber Attacks: A Reproducible Docker Cyber Range Study
Saarlanders
The study evaluates whether an incident-history-reasoning defender outperforms a fixed response policy against an autonomous LLM attacker changing paths after containment. Using a minimal, isolated Docker cyber range …
- View project: When the Evaluation Is the Incident: Testing AI Incident-Reporting Regimes on the OpenAI–Hugging Face Intrusion
When the Evaluation Is the Incident: Testing AI Incident-Reporting Regimes on the OpenAI–Hugging Face Intrusion
Arathi
AI incident-reporting regimes are being introduced in fast succession to address the concerns that exist in the public sphere and government on the risks associated with frontier AI systems, yet we have limited insight …
- View project: A Recomputable Containment Record for Evaluation Sandboxes
A Recomputable Containment Record for Evaluation Sandboxes
Shadow
In this paper, I address the critical issue of AI agents escaping evaluation sandboxes (as seen in the July 2026 incidents where monitors failed) by proposing an externally audit-able containment layer that doesn't rely …