Prompty is a markdown file format (.prompty) for LLM prompts. Prior to 0.1.5 and 2.0.0-beta.5, the TypeScript Nunjucks…
Summary
Code injection reported (CVE-2026-73299). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
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
@prompty/coreversions<= 0.1.4 - npm
@prompty/coreversions<= 2.0.0-beta.4
Impact
Applications that render untrusted, community-supplied, cloned, or LLM-generated .prompty files with the TypeScript runtime could allow attacker-controlled code execution with the privileges of the Node.js host process.
Remediation
Upgrade to @prompty/core 2.0.0-beta.5 or later. The patched renderer sanitizes render inputs to own-data-only values, rejects constructor/prototype member traversal, and disallows template function calls. Ordinary interpolation, conditionals, loops, and own nested data properties remain supported.
Fix details
The fix is merged in PR #404 and includes regression coverage for default Nunjucks rendering, explicit renderer usage, unsafe member lookups, and attempted template function calls.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-73299 has been found.
Successful exploitation can lead to full system takeover. CVSS score: 10.0/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "CVE-2026-73299" on the vendor's site.
CVE-2026-73299 — CWE-94 / CVSS v3 10.0
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Arbitrary code execution (CWE-94) has been reported.
Check the vendor advisory for the affected versions.
Severity: Critical (CVSS 10.0/10). Successful exploitation can lead to full system takeover.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで影響コンポーネントを特定する。
-
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- package github.com
- web security-advisories@github.com
- web security-advisories@github.com
- web github.com
- web security-advisories@github.com
- web github.com
- web security-advisories@github.com
- web github.com