CVE-2026-53597

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/microsoft/prompty/commit/c27402da2487075be577f06aa79df627fb9d6853
https://github.com/microsoft/prompty/security/advisories/GHSA-c4gh-rv8h-q9vw

Configurations

No configuration.

History

16 Jul 2026, 16:19

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-16 16:19

Updated : 2026-07-18 03:16

NVD link : CVE-2026-53597

Mitre link : CVE-2026-53597

CVE.ORG link : CVE-2026-53597

JSON object : View

Products Affected

No product.

CWE

CWE-94

Improper Control of Generation of Code ('Code Injection')

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