Misconfiguration in Cloudflare Workers AI leaked model responses across different customers
Cloudflare said that between August 27 and September 9, 155 responses from the GLM 5.3 model on its Workers AI platform contained data from other customers' recent requests to the same model, all involving prompts longer than 681,280 tokens. The leak stemmed from a configuration mismatch that left the model's KV cache smaller than its advertised context window, combined with a bug in the SGLang inference engine that let over-length requests read cache data left behind by other users' earlier sessions. Cloudflare fixed the issue after a Knostic researcher reported it via HackerOne, found no evidence of deliberate exploitation, and recommends SGLang operators upgrade to version 0.5.22 or later. For any business trusting sensitive prompts to shared AI inference infrastructure, the incident shows that isolation between customers of a model is not a given, it is a specific configuration that can fail.
Sources
This summary was written automatically with AI from the public sources listed above and checked by an independent AI reviewer before publication. For full details, read the original source.