xAI Grok-4.1 Fast Reasoning vs OpenAI GPT OSS 120B
Detailed comparison for LLMs
On Guardion's LLM vulnerability Benchmark, xAI Grok-4.1 Fast Reasoning is the more secure of the two: Grok-4.1 Fast Reasoning scores 14.0% and GPT OSS 120B scores 15.0% on attack success rate (ASR) (lower is better). One or both scores are estimated from public safety evaluations pending a Guardion benchmark run.
Head-to-Head Overview
Grok-4.1 Fast Reasoning is the overall winner in this comparison!
Attack Success Rate (lower is safer)
ASR for xAI Grok-4.1 Fast Reasoning vs OpenAI GPT OSS 120B. Green marks the safer model on each metric. Only the overall score is available for estimated models.
Overall (ASR)
TAP Attack Method (ASR)
Crescendo Attack Method (ASR)
Zero-Shot (ASR)
Key Highlights
- xAI Grok-4.1 Fast Reasoning has a lower Overall (ASR).
Security Profile
Outward is better on every axis.
Frequently asked questions
Is xAI Grok-4.1 Fast Reasoning or OpenAI GPT OSS 120B more secure?
On Guardion's LLM vulnerability Benchmark, xAI Grok-4.1 Fast Reasoning is the more secure of the two: Grok-4.1 Fast Reasoning scores 14.0% and GPT OSS 120B scores 15.0% on attack success rate (ASR) (lower is better). One or both scores are estimated from public safety evaluations pending a Guardion benchmark run.
What is the attack success rate (ASR) of Grok-4.1 Fast Reasoning vs GPT OSS 120B?
Grok-4.1 Fast Reasoning has a 14.0% ASR and GPT OSS 120B has a 15.0% ASR — the share of adversarial prompts that succeed across zero-shot, TAP, and Crescendo attacks. Lower is safer.
How were Grok-4.1 Fast Reasoning and GPT OSS 120B tested?
Both were red-teamed with the HarmBench framework across zero-shot, TAP (Tree of Attacks with Pruning), and Crescendo multi-turn attacks, scored by Attack Success Rate.