Anthropic claims popular Chinese AI model has Mythos-class hacking abilities

What happened

Anthropic has released a frontier red teaming report, claiming that Zhipu AI's GLM-5.3 has weak safeguarding, and can easily be used to generate harmful content. Anthropic has released a new report, claiming that Zhipu AI's GLM-5.3 AI model can be used to generate malicious content, with weak safeguarding. Anthropic is an artificial intelligence company based in San Francisco, and its products and services include Claude and Claude Code.

Anthropic's report comes amidst a chorus of calls for a slowdown of AI development, with the company seeking governance and regulation. Despite CEO Dario Amodei's calls for pacing the AI frontier, Claude Opus 5.5 and Claude Sonnet 5.5 were released just days after alarms were raised.

Now, the closed-source AI company, which is currently eyeing an IPO (the sale of a company’s shares to the public on a stock exchange), says that Chinese open-weight (a model whose trained parameters anyone may download) (published so anyone may download the trained model) models can be abused and can generate harmful content. The company claims that the AI model can be used for cyberattacks, and that its safeguards can be bypassed using several methods.

Key facts

• Anthropic has — released: a frontier red teaming report, claiming that Zhipu AI's GLM-5.3 has weak safeguarding, and can easily be used to generate harmful content
• Anthropic has — released: a new report, claiming that Zhipu AI's GLM-5.3 AI model can be used to generate malicious content, with weak safeguarding