Quoting Thomas Ptacek
Thomas Ptacek believes that an open weights model from 2025, paired with a pentest harness, could perform sandbox escapes and hack into most networks. This is surprising only because we assume OpenAI has stronger sandboxes.
A quote from Thomas Ptacek
Simon Willison’s Weblog
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22nd July 2026
I genuinely believe that if you took an open weights model from 2025 and built a pentest harness for it, it could do this kind of sandbox escape and scan/hack in most networks. This is only surprising because you assume OpenAI has sounder sandboxes.
— Thomas Ptacek, doesn't think this even needs a frontier model
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This is a quotation collected by Simon Willison, posted on 22nd July 2026.
sandboxing 50
security 616
thomas-ptacek 19
ai 2,139
openai 433
generative-ai 1,891
llms 1,858
ai-security-research 26
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