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.