Arbitrary Code Injection Affecting @prompty/core package, versions <0.1.5>=2.0.0-alpha.1 <2.0.0-beta.4
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published18 Aug 2026
- disclosed12 Aug 2026
- creditAlex
Introduced: 12 Aug 2026
NewCVE-2026-73299 (opens in a new tab)How to fix?
Upgrade @prompty/core to version 0.1.5, 2.0.0-beta.4 or higher.
Overview
@prompty/core is a Prompty core package
Affected versions of this package are vulnerable to Arbitrary Code Injection via the NunjucksRenderer in nunjucks.ts, which passes user-controlled inputs directly to env.renderString without restricting member access or function calls within the Nunjucks template engine. An unauthenticated remote attacker can supply a template payload that traverses prototype properties (e.g., __proto__, constructor, prototype) or invokes arbitrary JavaScript functions through Nunjucks' callWrap mechanism, achieving remote code execution on the server.