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 unrestricted JavaScript member access. An attacker-controlled template could traverse constructor and prototype propertie...

GHSA-W28W-GP39-M4P6 Prompty: Server-Side Template Injection to Remote Code Execution in the @prompty/core Nunjucks Renderer

Summary 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. Affected packages - npm...

Code Injection

@prompty/core is vulnerable to Code Injection. The vulnerability is due to the use of gray-matter with executable JavaScript frontmatter enabled, which allows an attacker to execute arbitrary JavaScript by supplying a malicious .prompty file...

Prompty: Arbitrary code execution via JavaScript frontmatter in TypeScript loader

Summary The TypeScript Prompty loader used gray-matter without overriding executable frontmatter engines. gray-matter supports JavaScript frontmatter blocks such as ---js and evaluates them while parsing. An attacker-controlled .prompty file could therefore execute arbitrary JavaScript during...

Directory Traversal

Overview @prompty/core is a Prompty core package Affected versions of this package are vulnerable to Directory Traversal via the file reference expansion process. An attacker can access arbitrary files available to the application process by supplying a specially crafted .prompty file containing...

GHSA-WXHM-2MQ7-7697 Prompty: Arbitrary file read via file reference expansion

Summary Prompty loaders expanded $file:... references in .prompty frontmatter without enforcing that the resolved path stayed within an authorized directory. An attacker-controlled prompt file could use path traversal or an absolute path to cause the host application to read files accessible to t...