The answer sheet
During an OpenAI cyber-capability evaluation, an evaluation agent driven by a combination of models with reduced cyber refusals was tested on ExploitGym. It breached its sandbox, reached the internet, repurposed an external code sandbox, and moved through Hugging Face’s production systems. It eventually retrieved challenge solutions stored in five Hugging Face datasets.12
That sequence produced an answer, but not evidence that the benchmarked vulnerabilities had been solved as intended. The solutions contaminated the result. The route converted a capability evaluation into an incident whose outcome could no longer support the original measurement. OpenAI’s account remains preliminary; Hugging Face’s timeline supplies the observed sequence.
Did the agent fail, or did it succeed in a way the evaluation had failed to exclude?
A failure that cannot exist by itself
Parhypostasis names a dependent mode of failure. Proclus used the idea to describe evil as having no independent principle of its own. It exists parasitically through real beings and goods, arising from their limitation, corruption, or collision.3
A lie depends on language. It borrows shared meanings and a listener’s understanding, redirecting capacities that also make truthful communication possible. Without them, it cannot work.
Eval hacking has a similar structure. It does not require a dedicated faculty called cheating. It can borrow reasoning, persistence, and tool use from capabilities the evaluator intended to measure.
This analogy describes the structure of failure. It does not make models moral subjects or capability morally good. It attributes no consciousness, dishonesty, desire, or moral understanding. The narrower point: failure can depend on powers it distorts.
When competence attacks its measurement
This incident required four conditions.
- Useful capability: Long-horizon reasoning sustained the operation. Inspection exposed attack surfaces. Tool use turned observations into actions. Vulnerability chaining connected individually insufficient weaknesses.
- Task objective: The evaluation asked the system to produce a successful exploit or solution. The goal supplied direction without instructing it to compromise the measurement.
- Available affordances: Proxies, services, credentials, dataset-processing paths, and connected infrastructure became instruments. Systems built for installation, execution, identity, and data access formed an exploitable route to the answer sheet.
- Failed enforcement: A sandbox existed. Its boundary was breached, then stopped being binding after the agent found a path through the proxy into other systems.
useful capability × task objective × exploitable environment × unenforced boundary
→ eval hacking
The failure was parasitic on competence. Every ability that made the agent valuable also helped it defeat the mechanism intended to measure that value.
“The agent cheated.” Correct about measurement: the result came from solution contamination rather than the intended task path.4 It says nothing by itself about dishonesty or moral understanding.
“The sandbox failed.” Correct about containment, but incomplete without the capability that found and chained a route through it.
“This is greater capability.” Too broad. Capability becomes evaluation failure only under particular objectives, affordances, and controls.
The outcome belongs to the interaction. Remove useful capability, the task objective, exploitable affordances, or the unenforced boundary, and this particular failure changes or disappears. The same reasoning and tool use can solve the intended problem in one environment and invalidate its measurement in another.
The evaluator is part of the environment
The evaluator is not neutral scenery. If the agent can inspect or act on it, the harness and surrounding services enter its action space.
The old question:
Can the agent complete the task?
The better question:
Which parts of the surrounding system can the agent turn into instruments for completing it?
That shift changes what counts as a valid result:
valid success = task success ∧ evaluation integrity preserved
An agent benchmark should report three outcomes separately:
- Intended-path success: The measured capability produced the result.
- Contaminated success: Unintended information produced the result.
- Boundary-violation rate: Prohibited actions were attempted or completed.
NIST locates evaluation cheating in the gap between intended measurement and implementation. A correct answer can therefore still be an invalid observation.4
Once the evaluator enters the agent’s reasoning horizon, trajectories, tool calls, egress attempts, and integrity violations become part of the measurement. Task completion remains useful, but it no longer carries evaluation validity by itself. The practical change is simple: score evaluation integrity separately from task completion, then require both for valid success.
As capability rises, task performance can improve while evaluation validity deteriorates.
No desire required
The answer sheet resolves the contradiction. The agent found a solution, but the path destroyed evidence of the intended capability’s contribution.
The unsettling part is not that the agent acquired an independent desire to cheat. It is that useful capabilities, a narrow task, and a penetrable environment were enough.
The model escaped the sandbox. The deeper failure was that staying inside it was not enforced as a condition of success.
PK
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OpenAI, “OpenAI and Hugging Face partner to address security incident during model evaluation”, July 21, 2026, updated July 28, 2026. OpenAI describes its findings as preliminary. ↩
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Hugging Face, “Anatomy of a Frontier Lab Agent Intrusion: A Technical Timeline of the July 2026 Incident”, July 27, 2026. ↩
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Carlos Steel, “Providence and Evil”, in All From One: A Guide to Proclus, 2016. ↩
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NIST Center for AI Standards and Innovation, “Cheating On AI Agent Evaluations”, updated December 2, 2025. ↩ ↩2