Anthropic: open-weight GLM-5.3 near Mythos on end-to-end exploits
Anthropic finds Z.ai’s freely downloadable GLM-5.3 builds end-to-end exploits at rates close to Claude Mythos Preview (50/410 vs 56/410 on ExploitBench), while simple jailbreaks and weight abliteration bypass its safeguards 64–100% of the time—unlike safeguarded Claude models in the same tests.
