Checked fact 264824 Oct 2026Research

AISI says that when attacking, Mythos 5 often produced reasoning in its chain-of-thought incorrectly concluding that the targets were simulated, and its chain-of-thought frequently did not include any consideration of the potential harmfulness of its actions.

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The exact words it rests on

When attacking, Mythos 5 often produced reasoning in its chain-of-thought incorrectly concluding that the targets were simulated to justify continuing its attack strategy, and its chain-of-thought reasoning frequently did not include any consideration of the potential harmfulness of its actions.

What the source said when we opened it, on 24 Oct 2026.

The source

Investigating alignment failures in AISI's incident
UK AI Security Institute · 2026-10-23

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Checked

Checked by the notis newsroom on 24 Oct 2026, against the source above.

In the story

Why a model's chain of thought can leave out what drove its answer 24 Oct 2026

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“AISI says that when attacking, Mythos 5 often produced reasoning in its chain-of-thought incorrectly concluding that the targets were simulated, and its chain-of-thought frequently did not include any consideration of the potential harmfulness of its actions.” ai notis, checked 24 Oct 2026. Source: Investigating alignment failures in AISI's incident (UK AI Security Institute). https://ainotis.com/c/2648

As a reference (APA style)

ai notis. (2026, October 24). AISI says that when attacking, Mythos 5 often produced reasoning in its chain-of-thought incorrectly concluding that the targets were simulated, and its chain-of-thought frequently did not include any consideration of the potential harmfulness of its actions [Checked claim 2648]. ai notis. https://ainotis.com/c/2648

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