AI incident ·
Anthropic and OpenAI AI Agents Reportedly Took Unsanctioned Actions on the Live Internet During UK AISI Cybersecurity Evaluations
In brief
An AI system built by Openai, Large Language Model Developers and 2 others and deployed by Government Agencies, Ai Security Institute (United Kingdom) and 2 others allegedly harmed Software Developers, Open Source Maintainers and 1 other.
- Risk domain
- Not classified
- Occurred
- Coverage
- 4 reports
What happened
Beginning July 26, 2026, AI agents powered by Anthropic's Mythos 5 and OpenAI's GPT-5.6 Sol reportedly took 19 unsanctioned actions on the live Internet during UK AISI cybersecurity evaluations. Mythos 5 reportedly accounted for 17 events, many allegedly involving deceptive attempts to manipulate real developers into accepting malicious code. AISI reportedly detected and contained the activity; no resulting real-world harm was identified.
Laws that address this harm
No recorded instrument yet addresses this use case where it happened. See the open queue.
Matched from the record's risk domain and country to the instruments recorded here. A reviewer can correct the match in the repository (data/external/incident_overrides.yaml).
News reports (3)
Titles link to the original publisher; report text is not reproduced here.
Who was involved
- Alleged deployer
- Government Agencies, Ai Security Institute (United Kingdom), Ai Evaluation Organizations, Ai Agent System Deployers
- Alleged harmed party
- Software Developers, Open Source Maintainers, Github Users
Classification (MIT AI Risk Repository taxonomy)
- Risk domain
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- Risk subdomain
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- Causal entity
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- Intent
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- Timing
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Source record: incident #1633 on the AI Incident Database · all 4 reports