GLM-5.3 is here with advanced cyber capabilities — and reportedly already found a 'serious vulnerability' in Cursor

Chinese AI startup Z.ai, known internationally for its growing lineup of powerful, largely open source GLM series of language models, today released GLM-5.3 with substantial gains in long-horizon coding and a more consequential — and potentially sensitive — jump in cybersecurity capabilities.Already, GLM-5.3's cyber capabilities have found a "potentially serious vulnerability in Cursor," the AI coding startup recently acquired by SpaceX, according to z.ai developer advocate Lou, posting on X. VentureBeat also tagged Cursor for confirmation on X and is awaiting response.GLM-5.3 is available initially only through the company's GLM Coding Plan and ZCode coding environment, while API access and open weights are coming later, "once safety evaluation and hardening are complete," according to th