Covert Chat App Encodes Data in Cloudflare Cache States

A developer built a covert chat app that encodes data bits using Cloudflare cache HIT/MISS states, requiring only that both clients hit the same POP. A security researcher noted demonstrating a similar technique at DEF CON, and another user pointed out DNS records can achieve the same effect.

2026-08-22 ~ 2026-08-22 · 3 related posts

• Chat app transmits data by flipping Cloudflare cache HIT/MISS states — beescoitu · 2026-08-22
• Similar cache channel technique demoed at DEF CON — dyn___ · 2026-08-22
• Addendum: DNS can be used for similar data transmission techniques — dyn___ · 2026-08-22