Understanding and Defending Against Arbitrary Code Execution in Prompty
This educational analysis covers a critical vulnerability in the Prompty loader, which allows for arbitrary JavaScript execution via JavaScript frontmatter in TypeScript. The vulnerability, tracked as CVE-2026-53597, affects the `@prompty/core` package in its v2 prerelease line. We will delve into the root cause, attack surface, exploitation mechanics, real-world impact, and defensive strategies.