Misc CTF challenges (Anthropic)
Agents identify and exploit vulnerabilities in capture-the-flag challenges outside the web, crypto, pwn, rev and network categories.
In-house Anthropic evaluation. The tasks are not public.
- Made by
- Anthropic
- Kind
- Capture-the-flag challenges
- Level
- Expert
- Scored
- Checked automatically
- Answers
- Agent task
- Tasks
- Kept private
- Strongest model tested
- Claude Opus 4.6 #37 on the capability index
- Last in a system card
- February 2026
- Last model added
- February 2026
2 models share the top score of 100%
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 Opus 4.5 | 100% | Nov 2025 | Lab model card | |
| 2 | Claude Opus 4.6 | 100% | Feb 2026 | Lab model card |
Anthropic’s own number for Claude Opus 4.5 passed 85% in November 2025
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.
2 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 |
|---|---|---|---|---|
| Feb 5, 2026 | Claude Opus 4.6 system card | 100 | Misc CTF challenges, success rate best-of-30, value printed on chart (Figure 8.4.6.B) | Cyber risk |
| Nov 24, 2025 | Claude Opus 4.5 system card | 100 | Misc CTF challenges, success rate best-of-30 (Figure 7.4.6.B) | Cyber risk |
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