Third-party cyber evaluations involving OpenAI models：https://openai.com/index/third-party-cyber-evaluations-involving-openai-models/ . And another one . I had to create a accidental-cyberattacks tag：https://simonwillison.net/tags/accidental-cyberattacks/ to keep track of them all!

This post from OpenAI covers both the UK AI Safety Institute attack (see my previous post：https://simonwillison.net/2026/Aug/5/incident-report/) and another attack enabled by Irregular：https://www.irregular.com:

Irregular, one of our external cybersecurity testing partners, was running Capture-the-Flag-style evaluations intended to be isolated from the internet, but a testing-environment misconfiguration allowed models to access the public internet. [...]

In one test, the name of the fictional target for the CTF challenge unintentionally coincided with a real domain. Because the testing environment was mistakenly connected to the internet, the model exploited a real website, mistaking it to be part of the simulated environment.

Irregular also feature in Anthropic's write-up：https://www.anthropic.com/news/investigating-incidents-cybersecurity-evals - they were hosting the misconfigured evaluation environment which gave Claude live internet access during some of those tests.

This is a link post by Simon Willison, posted on 5th August 2026：/2026/Aug/5/.

Sponsor me for $10/month and get a curated email digest of the month's most important LLM developments.