https://vulnerability.circl.lu Contains only the most 10 recent entries. http://www.rssboard.org/rss-specification python-feedgen en Thu, 01 Oct 2026 16:42:41 +0000 https://vulnerability.circl.lu/vuln/fkie_cve-2026-53597 <p>Prompty is a markdown file format (.prompty) for LLM prompts. From 2.0.0-alpha.1 until 2.0.0-beta.3, the @prompty/core TypeScript loader in runtime/typescript/packages/core/src/core/loader.ts used gray-matter without overriding executable js and javascript frontmatter engines, allowing an attacker-controlled .prompty file with ---js frontmatter to execute arbitrary JavaScript during prompt loading. This issue is fixed in version 2.0.0-beta.3.</p> <p>Prompty is a markdown file format (.prompty) for LLM prompts. From 2.0.0-alpha.1 until 2.0.0-beta.3, the @prompty/core TypeScript loader in runtime/typescript/packages/core/src/core/loader.ts used gray-matter without overriding executable js and javascript frontmatter engines, allowing an attacker-controlled .prompty file with ---js frontmatter to execute arbitrary JavaScript during prompt loading. This issue is fixed in version 2.0.0-beta.3.</p> https://vulnerability.circl.lu/vuln/fkie_cve-2026-53597 https://vulnerability.circl.lu/vuln/ghsa-c4gh-rv8h-q9vw <p><strong>Affected:</strong> npm: @prompty/core</p> <p>## 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 prompt loading.</p> <p>## Affected package - npm `@prompty/core` v2 prerelease line: `&gt;= 2.0.0-alpha.1 &lt; 2.0.0-beta.3` - Fixed in `@prompty/core@2.0.0-beta.3`</p> <p>The legacy v1 JavaScript runtime had a historical hardening change for this issue. During the v2 TypeScript runtime rebuild, the loader again called `gray-matter` directly and the vulnerable behavior was present in the v2 prerelease packages until `2.0.0-beta.3`.</p> <p>## Impact Applications that load untrusted `.prompty` files, user-provided prompt paths, or prompt bundles from less-trusted locations could execute arbitrary JavaScript in the host Node.js process during frontmatter parsing.</p> <p>## Remediation Upgrade `@prompty/core` to `2.0.0-beta.3` or later.</p> <p>The fix explicitly overrides the `js` and `javascript` gray-matter engines and rejects JavaScript frontmatter in `.prompty` files. Prompty frontmatter is YAML-only; executable frontmatter is unsupported. A regression test now verifies that `---js` frontmatter is rejected and not evaluated.</p> <p>## Fix details Fixed by commit `c27402da2487075be577f06aa79df627fb9d6853` and released via `typescript/2.0.0-beta.3`.</p> <p><strong>Affected:</strong> npm: @prompty/core</p> <p>## 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 prompt loading.</p> <p>## Affected package - npm `@prompty/core` v2 prerelease line: `&gt;= 2.0.0-alpha.1 &lt; 2.0.0-beta.3` - Fixed in `@prompty/core@2.0.0-beta.3`</p> <p>The legacy v1 JavaScript runtime had a historical hardening change for this issue. During the v2 TypeScript runtime rebuild, the loader again called `gray-matter` directly and the vulnerable behavior was present in the v2 prerelease packages until `2.0.0-beta.3`.</p> <p>## Impact Applications that load untrusted `.prompty` files, user-provided prompt paths, or prompt bundles from less-trusted locations could execute arbitrary JavaScript in the host Node.js process during frontmatter parsing.</p> <p>## Remediation Upgrade `@prompty/core` to `2.0.0-beta.3` or later.</p> <p>The fix explicitly overrides the `js` and `javascript` gray-matter engines and rejects JavaScript frontmatter in `.prompty` files. Prompty frontmatter is YAML-only; executable frontmatter is unsupported. A regression test now verifies that `---js` frontmatter is rejected and not evaluated.</p> <p>## Fix details Fixed by commit `c27402da2487075be577f06aa79df627fb9d6853` and released via `typescript/2.0.0-beta.3`.</p> https://vulnerability.circl.lu/vuln/ghsa-c4gh-rv8h-q9vw