Cross-request KV cache exposure in the GLM-5.3 Workers AI model, and our remediation with SGLang
- On September 8, 2026, we were alerted by a security researcher, Gadi Evron from Knostic, to a tenant isolation issue affecting the GLM-5.3 Workers AI model (@cf/zai-org/glm-5.3) starting on August 27, 2026.
- We have remediated the issue, and we restored the model on September 9.
- We have confirmed that no other model hosted on Workers AI was affected.
Unverified
- On September 8, 2026, we were alerted by a security researcher, Gadi Evron from Knostic, to a tenant isolation issue affecting the GLM-5.3 Workers AI model (@cf/zai-org/glm-5.3) starting on August 27, 2026.
- We have remediated the issue, and we restored the model on September 9.
- We have confirmed that no other model hosted on Workers AI was affected.
Sources: Cloudflare