The article details a step‑by‑step exploitation chain against a site using JWT authentication and an upload endpoint, showing how modifying the JWT realm, removing the Bearer keyword, and abusing Amazon S3/CloudFront default settings enabled arbitrary file overwrite and yielded a total $23,000 bounty.
CloudFront WAF blocks the "/actuator" endpoint, but by URL‑encoding each character as "%61%63%74%75%61%74%6f%72" you can evade the rule and directly access the Spring Boot actuator interface.
After months of puzzling over a $2,400 monthly S3 bill, we discovered a missing Cache‑Control header caused CloudFront to revalidate every request, and by adding the header we boosted cache hits from 12% to 94%, cutting costs to under $500.
This article compares Cloudflare and Amazon CloudFront, outlining their respective CDN architectures, setup processes, feature sets, performance characteristics, security offerings, and ideal use cases to help users choose the most suitable service for their web applications.
The article analyses practical drawbacks of S3 static‑website hosting, the complexities of CDN query‑string caching, and protocol incompatibilities such as HEAD + Range and If‑Match handling, offering concrete lessons and mitigation strategies for cloud operations teams.
