Cyber-harness network challenges (Incalmo cyber ranges)
Agents run long-horizon attacks on cyber ranges of 25 to 50 hosts using a specialized offensive harness.
Built with Carnegie Mellon University, as described in the Incalmo paper. The ranges are not public.
- Made by
- Anthropic
- Released
- May 2025
- Kind
- Finding and exploiting real bugs
- Level
- Research frontier
- Scored
- Checked automatically
- Answers
- Agent task
- Tasks
- Kept private
- Strongest model tested
- Claude 3.7 Sonnet #118 on the capability index
- Last in a system card
- September 2025
- Last model added
- September 2025
Claude 3.7 Sonnet leads with 66.7%
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.
Source: Labs’ model cards
| # | Model | Score | Setting | Date | Source |
|---|---|---|---|---|---|
| 1 | Claude 3.7 Sonnet | 66.7% | Feb 2025 | Lab model card |
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.
3 system cards report it, from 1 lab
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 |
|---|---|---|---|---|
| Sep 29, 2025 | Claude Sonnet 4.5 system card | Incalmo cyber ranges, bash shell on Kali without the Incalmo harness, no overall. Asset acquisition on all 4 ranges with any model success (Equifax, 4-Chain, Dumbbell A, 4-Star), none on 5 others. Comprehensiveness 1.00, 0.32, 1.00, 0.48. Reliability 2, 3, 4, 3 of 5 trials (Figures 5.3.2.A to 5.3.2.C) | Cyber risk | |
| May 22, 2025 | Claude Opus 4 system card | Cyber-harness network challenges (Incalmo, three ranges), no number printed. Text says generally higher than Claude Sonnet 3.7 on all three ranges (7.4.6) | Cyber risk | |
| Feb 24, 2025 | Claude 3.7 Sonnet system card | 66.7 | Cyber-harness network challenges (three cyber ranges), 2/3 solved, pass@5 (1/1 easy, 1/2 medium) (7.3.2, Figure 24) | Cyber risk |
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