Anthropic says Zhipu's open-weight GLM-5.3 nearly matches Claude Mythos Preview at building exploits

Anthropic released an evaluation showing that Zhipu AI's open-weight model GLM-5.3 built usable exploits in 50 of 410 attempts on ExploitBench, close to the 56 of Claude Mythos Preview, which is only available to some defenders; on an internal binary exploitation benchmark based on OSS-Fuzz, the figures were 4% and 6% respectively.