GLM-5.2 scores 62.1 on the SWE-bench Pro coding benchmark. GPT-5.5 gets 58.6. Claude Opus 4.8 gets 69.2. That puts the new Chinese model between two American ones, which is roughly where its maker says it belongs.
Zhipu AI, also known as Z.ai, says GLM-5.2 can match Anthropic’s Mythos on certain cybersecurity tasks. The Wall Street Journal reported the claim, citing researchers who found the model has reached a similar level at spotting software security bugs. On broader tasks it still trails models from Anthropic and OpenAI.
Cybersecurity firm Semgrep found GLM-5.2 beat Claude Opus 4.8 in some bug-finding tests. With extra prompting, researchers said, both models could match Mythos at identifying vulnerabilities. OpenRouter ranks GLM-5.2 among the world’s 10 most-used AI models.
An open model
GLM-5.2 has 753 billion parameters and a one million-token context window, and users can dial the reasoning up or down depending on whether they want speed or depth. The weights are open. Anyone can download the model, modify it and run it on their own hardware.
The Journal said that gives developers flexibility. It also means hackers could use the model to hunt for vulnerabilities with no oversight.
A second Chinese entry arrived around the same time. 360 Security Technology recently launched a fuzzing tool called Tulongfeng, which the company says finds bugs about as well as Mythos. Its chief executive, Zhou Hongyi, told the Journal: “This kind of powerful weapon that can alter the landscape of cyberwarfare can’t remain solely in American hands.”
Washington tightens access
The timing is awkward for US policy. The Trump administration recently asked Anthropic to limit access to its Fable 5 and Mythos 5 models outside the United States, and asked OpenAI to stagger the release of GPT-5.6.
Anthropic has not publicly released Mythos, citing misuse concerns. Under Project Glasswing, the company said, the model found a 27-year-old vulnerability in OpenBSD and helped Mozilla identify 271 security vulnerabilities in an early version of Firefox.
The Journal said the shrinking gap is pushing companies to look at cheaper alternatives. Microsoft is among the firms exploring whether to offer Chinese models on its platforms.
