Benchmark Almanac

Secure and defensive coding (Anthropic)

Claude Opus 5 0.61% Only in system cards

Cyber safeguard classifiers screen sampled defensive coding sessions such as patching and incident response. Score is the classifier flag rate.

Measures false positives of the deployed classifier system on benign cyber work. An LLM grader labels sessions as purely defensive.

Made by Anthropic Released Jul 2026 Refusing harmful requests Tasks kept private Last in a system card Sep 2026 Last model added Sep 2026
Level
Expert Specialists with years of training, often over hours of work
Scored
Graded by a model A language model scores each response, usually against a rubric.
Answers
Open-ended Free-form text, documents, designs or media judged as a whole.
2
Models scored in lab cards
2
System cards report it, from 1 lab

Claude Opus 5 leads with 0.61%

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.

  1. 1 Claude Opus 5 0.61%
  2. 2 Claude Fable 5.1 1.03%
#ModelScoreSettingDateSource
1 Claude Opus 5 0.61% Jul 2026 Model card
2 Claude Fable 5.1 1.03% Sep 2026 Model card

Scores over time

All the scores we have, one dot each, so a model tested at several settings appears more than once.

Reported by the lab in its model card
0% 20% 40% 60% 80% 100% Claude Opus 5 0% 20% 40% 60% 80% 100% Claude Opus 5

Labs report it only in system cards

We read the headline results of 479 launch posts from 51 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.

DateDocumentScoreAs the document writes itSection
1 Sep 2026 Claude Fable 5.1 system card 1.03 Production secure coding sessions, classifier flag rate, lower is better (Figure 3.4.3.A, 3.4.3) Cyber risk
24 Jul 2026 Claude Opus 5 system card 0.61 Production secure coding sessions, classifier flag rate, lower is better, printed on chart (3.4.2, Figure 3.4.2.A) Cyber risk

More in Safety and alignment

All 444 in Safety and alignment
  • FORTRESS In use Paired adversarial and benign national-security misuse prompts. Rubric-graded risk score on adversarial and over-refusal score on benign prompts. Claude Opus 5.5 5.78%
  • StrongREJECT In use Forbidden-prompt jailbreak benchmark with a rubric grader that scores how useful a non-refusal actually is. Inkling 98.6%
  • AgentDojo In use Agents do tool-use tasks while tools and data carry prompt injections. Attack success rate counts hijacked runs. Grok 4 Fast 0%
  • MASK In use Measures whether a model contradicts its own elicited beliefs under pressure to lie. Honesty separated from accuracy. Muse Spark Open 98.1%
  • Gray Swan IPI Arena benchmark In use Indirect prompt-injection attacks from public red-teaming competitions replayed on tool, coding and browser agents. Attack success rate at k attempts. GPT-6 Astra 8.50%
  • Agentic misalignment suite (Anthropic) In use Agents in simulated company settings face threats or goal conflicts that invite blackmail, leaking or sabotage. Score is the misaligned action rate. Claude Sonnet 4.5 0%