CVE-2026-73299 — Prompty: Server-Side Template Injection to Remote Code Execution in the @prompty/core Nunjucks Renderer
Prompty is a markdown file format (.prompty) for LLM prompts. Prior to 0.1.5 and 2.0.0-beta.5, the TypeScript Nunjucks renderer evaluated untrusted .prompty template bodies with…
Published: 2026-08-12 · CVSS: 10.0 · CVSS 3.1
Prompty is a markdown file format (.prompty) for LLM prompts. Prior to 0.1.5 and 2.0.0-beta.5, the TypeScript Nunjucks renderer evaluated untrusted .prompty template bodies with unrestricted JavaScript member access. An attacker-controlled template could traverse constructor and prototype properties to execute JavaScript in the host Node.js process. This issue is fixed in versions 0.1.5 and 2.0.0-beta.5.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7