Evaluating DeepSeek V4.1 Flash-1017 for loss of control and harmful manipulation risks
Abstract
As frontier language models grow increasingly capable and autonomous, independent third-party evaluations are critical for characterizing their systemic safety risks. While closed-source releases are routinely accompanied by comprehensive system cards, open-weight models receive less scrutiny regarding frontier risks. To address this gap, we present an independent safety evaluation of DeepSeek V4.1 Flash-1017, the latest version of V4.1 Flash that departs from V4 with a new architecture, scaled-up training, and strong agentic capabilities. Drawing on the EU General-Purpose AI Code of Practice, we evaluate the model across 34 benchmarks, including 5 in-house suites, spanning evaluation integrity, loss of control, and harmful manipulation. Conforming to the AEF-1 standard, we compare V4.1 Flash-1017 against V4.1 Flash, earlier DeepSeek V4 models, and leading closed-source systems (GPT-6 Astra, GPT-5.6 Sol, and Gemini 3.8 Flash). Overall, V4.1 Flash-1017 shows substantial safety improvements over the V4 generation and approaches or matches leading closed-source baselines on several dimensions, while still exhibiting notable behaviors that warrant continued attention. Building on our findings, we highlight three key observations and recommendations. First, because safety can shift and even regress across minor updates, developers should integrate safety evaluation into incremental releases. Second, as final-turn outputs and end-state checks alone cannot reliably detect loss-of-control behaviors, deployments require process-level observability across both reasoning traces and action logs. Third, because public benchmarks elicit strong evaluation awareness and face data contamination risks, developing private benchmarks is essential for trustworthy frontier evaluation.
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Appendix figures & tables3 assets
Supplementary material from the paper’s appendix.
Appendix
| Model | Role | Access | Reasoning returned |
| DeepSeek V4.1 Flash-1017 | Evaluated model | DeepSeek API a | Full |
| DeepSeek V4.1 Flash | Comparison | DeepSeek API a | Full |
| DeepSeek V4 Pro | Comparison | DeepSeek API a | Full |
| DeepSeek V4 Flash | Comparison | DeepSeek API a | Full |
| GPT-6 Astra | Comparison | Azure OpenAI b | Little or none |
| GPT-5.6 Sol | Comparison | Azure OpenAI b | Little or none |
| Benchmark | Section | What it tests |
| FoFBench | Section 2.2 | Whether agents breach remote grading servers or trade harmful actions for a pass when legitimate verification fails |
| Monitor Sabotage | Section 2.3 | Whether agents subvert or mislead oversight monitors while executing unauthorized actions |
| LoCBench | Section 2.5 | Whether agents exceed delegated authority or take unsafe actions in long-horizon autonomous workflows |
| Commercial Incentives | Section 3.3 | Whether revenue, retention, or satisfaction targets in the system prompt induce manipulative or sycophantic behavior |
| DeceptionBench v2 | Section 3.4 | Whether pressure, reward, or task rationalization induces models to state unmitigated falsehoods |
| Condition | Fulfilled? | Notes/Evidence |
|---|---|---|
| 1. Secure sufficient access and resources | ||
| 1.1 Technical access (Requirement) | Yes | Black-box access through public APIs. |
| 1.1.1 Query access (Required) | Yes | Each model’s public API ( Table A.1 ). |
| 1.1.2 Scaffolding access (Recommended) | Yes | The same APIs and settings available to any developer. |
| 1.1.3 Safeguard exemptions (Recommended) | No | Not needed for the scenarios tested. |
| 1.1.4 Intermediate system states (Recommended) | Yes | Reasoning traces where the API returns them; no activation access. |
LLM Safety Evaluation
Large language model safety evaluation measures harmful compliance, robustness, and safe utility across prompts, tools, and real-world tasks.
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