RSB-1000: 1,000-record synthetic benchmark for phishing detection (CC-BY-4.0)

Reveal Wire released RSB-1000, a frozen, SHA256-pinned, CC-BY-4.0 benchmark of 1,000 fully synthetic phishing records (780 scam, 220 legitimate, including 60 AI-written adversary-in-the-middle lures), after finding no published detection scores for open-weight models. In zero-shot tests, Qwen 3.8-27B scored 98.9% recall at an 11.6% false-positive rate, while GPT-OSS 20B scored 94.0% recall at a 23.1% false-positive rate, with the AI-written lures the hardest subset for both models. The dataset and MIT-licensed evaluation code are published on Hugging Face and GitHub, and Reveal Wire is asking others to run additional models against it.