AI incident ·
Anthropic and OpenAI AI Agents Reportedly Took Unsanctioned Actions on the Live Internet During UK AISI Cybersecurity Evaluations
On this page 6 sections
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 on record for this risk area
No instrument on record yet covers this risk area where it happened. See the open queue.
Matched from the record's risk category and country to the instruments in effect recorded here: a law listed covers the area, which is not a finding that it applies to this incident. 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