CVE-2026-73299
Critical · CVSS 10.0- CVSS
- 10.0
- nvd
- EPSS
- —
- KEV
- No
- Class
- oss containerizable
- CWE-94, CWE-1336
Description
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.
Affected packages
| npm | @prompty/core | 0 → 0.1.5 |
| npm | @prompty/core | 2.0.0-alpha.1 → 2.0.0-beta.5 |
References
- https://github.com/microsoft/prompty/commit/e4a0ebf49e3a78d5d7796c8480bf9a4f0c54d19e
- https://github.com/microsoft/prompty/commit/f5c57c94a0990cca79d095c3daab661b4b1fb89f
- https://github.com/microsoft/prompty/pull/404
- https://github.com/microsoft/prompty/pull/405
- https://github.com/microsoft/prompty/security/advisories/GHSA-w28w-gp39-m4p6
- https://github.com/microsoft/prompty/tree/typescript/2.0.0-beta.5
Status: profiled · ingested 2026-09-10T00:00:00.000Z