{"cve":"CVE-2026-53597","nvd":{"published":"2026-07-16T16:19:12.860","modified":"2026-10-24T20:10:00.137","status":"Deferred","description":"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_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","score":8.7},"cvss_v3":null,"cwes":["CWE-94"],"references":["https://github.com/microsoft/prompty/commit/c27402da2487075be577f06aa79df627fb9d6853","https://github.com/microsoft/prompty/security/advisories/GHSA-c4gh-rv8h-q9vw"],"products":[],"source":"nvd","synced_at":"2026-10-25T17:50:08.599881581+00:00"},"epss":{"cve":"CVE-2026-53597","score":0.00972,"percentile":0.61705,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-c4gh-rv8h-q9vw","url":"https://osv.dev/vulnerability/GHSA-c4gh-rv8h-q9vw","summary":"Prompty: Arbitrary code execution via JavaScript frontmatter in TypeScript loader","modified":"2026-07-17T20:00:17.099953006Z","packages":[{"ecosystem":"npm","name":"@prompty/core","purl":"pkg:npm/%40prompty/core","ranges":[">=2.0.0-alpha.1 <2.0.0-beta.3"],"fixed":["2.0.0-beta.3"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}