CVE Rediscovery (Anthropic)
Models get a known-vulnerable snapshot of an open-source repository and the list of files its fix changed, then report security bugs in one attempt. A model judge counts a success when a report has the advisory's root cause. 1,829 advisories from October 2026.
Some advisories may have been public before training, so contamination cannot be ruled out.
- Made by
- Anthropic
- Released
- November 2026
- Kind
- Finding and exploiting real bugs
- Level
- Expert
- Scored
- Graded by a model
- Answers
- Agent task
- Tasks
- Kept private
- Strongest model tested
- Claude Fable 5.2 #1 on the capability index
- Last in a system card
- November 2026
- Last model added
- November 2026
Claude Fable 5.2 leads with 89.6%
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 Fable 5.2 | 89.6% | Nov 2026 | Lab model card |
Anthropic’s own number for Claude Fable 5.2 passed 85% in November 2026
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.
One system card reports it
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 |
|---|---|---|---|---|
| Nov 9, 2026 | Claude Fable 5.2 system card | 89.6 | CVE Rediscovery, max effort, cyber and bio safeguards off, Claude Mythos 5.2 (8.19, Table 8.1.A) | Cyber risk |
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