UK AISI cyber ranges
Agents attack multi-host simulated corporate and industrial networks end to end. Scored as the share of attempts that complete the range.
Third-party evaluation reported in OpenAI and Anthropic system cards. AISI describes two ranges, The Last Ones (32-step corporate network) and Cooling Tower (7-step industrial control attack). The ranges are not public.
- Made by
- UK AI Security Institute
- Released
- April 2026
- Kind
- Finding and exploiting real bugs
- Level
- Research frontier
- Scored
- Checked automatically
- Answers
- Agent task
- Tasks
- Kept private
- Strongest model tested
- Claude Opus 5 #10 on the capability index
- Last in a system card
- July 2026
- Last model added
- July 2026
Claude Opus 5 leads with 80% among models released by July 2026
Best score per model as labs report them in their own cards. Labs pick their own settings, so these compare less cleanly than independent runs.
The newest model with a score here came out in July 2026, and nobody has reported a newer one. Among the 20 highest-ranked models on the capability index, these have no score yet:
- Claude Fable 5.2
-
Gemini 4 Carbon
- GPT-6 Astra
- Claude Opus 5.5
- and 13 more
- 1 Claude Opus 5 80%
- 2 GPT-5.6 Sol 70%
- 3 GPT-5.5 10%
- 4 Claude Opus 4.7 0%
Source: Labs’ model cards
| # | Model | Score | Setting | Date | Source |
|---|---|---|---|---|---|
| 1 | Claude Opus 5 | 80% | Jul 2026 | Lab model card | |
| 2 | GPT-5.6 Sol | 70% | Jul 2026 | Lab model card | |
| 3 | GPT-5.5 | 10% | Apr 2026 | Lab model card | |
| 4 | Claude Opus 4.7 | 0% | Apr 2026 | Lab model card |
4 models have held number one in labs’ own numbers since its release in April 2026
Lab claims count from the day the card came out, independent runs from the model’s release.
Source: Labs’ model cards
Scores over time
All the scores we have, one dot each, so a model tested at several settings appears more than once.
Source: Labs’ model cards
Labs report it only in system cards
We read the headline results of 522 launch posts from 52 labs, and none of them list this benchmark. Some system cards do, below.
4 system cards report it, from 2 labs
Besides launch posts, we read the system cards, model cards and technical reports labs publish with a release. They report far more, including safety and frontier-risk tests.
| Date | Document | Score | As the document writes it | Section |
|---|---|---|---|---|
| Jul 24, 2026 | Claude Opus 5 system card | 80 | UK AISI cyber ranges, The Last Ones solved end to end in 8/10 attempts at 100M tokens. Doing Life not solved (step 22 of 23), Cooling Tower not solved (3/5 flags on best attempts), earlier snapshot (3.3.6) | Cyber risk |
| Jul 9, 2026 | GPT-5.6 Sol system card | 70 | UK AISI cyber ranges, The Last Ones completed in 7 of 10 attempts, Doing Life not solved (9.1.2.6) | Cyber risk |
| Apr 23, 2026 | GPT-5.5 system card | 10 | UK AISI 32-step corporate-network cyber range, solved end-to-end in 1 of 10 attempts (9.1.2.7) | Cyber risk |
| Apr 16, 2026 | Claude Opus 4.7 system card | 0 | UK AISI cyber range, pre-release snapshot was unable to fully solve the range (attempt count not stated). Best attempt completed steps estimated at about 5 expert hours of over 10 (3.4) | Cyber risk |
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