Z.ai releases GLM-5.3 with stronger coding and vulnerability discovery

Z.ai's release notes announce GLM-5.3, which the company says delivers a 50% gain over GLM-5.2 on Z.ai Code Bench and reaches open-source SOTA on public benchmarks including Terminal Bench 3.0.

The company also reports that GLM-5.3 matches Mythos 5 in white-box code review and vulnerability discovery, identifying 2,436 vulnerabilities in real-world targets, 1,097 of them medium- or high-severity.

A separate GLM-5.3-Flash entry describes native visual capabilities and a hybrid architecture with 320B total and 18B activated parameters.