EP. 168: Cloudflare Container Flaw Exposed Data Across Customer Environments

The Digital Warfare Podcast · Sep 28, 2026 · 4m · transcript

Summary

Fresh reporting published September 27 details a vulnerability affecting Cloudflare Containers and Sandboxes that could allow a customer with a Workers Paid account to recover residual data from storage blocks previously used by other customers on the same underlying host.

The underlying issue involved a shared storage pool configured to skip zeroing reused 64 KiB blocks. Researchers demonstrated that writing 4 KiB to a newly allocated block could leave the remaining portion containing readable residual information from a previous workload. Potentially recoverable material included…