Instituto Nacional de ciberseguridad. Sección Incibe
Instituto Nacional de Ciberseguridad. Sección INCIBE-CERT

CVE-2026-33941

Gravedad CVSS v3.1:
ALTA
Tipo:
CWE-79 Neutralización incorrecta de la entrada durante la generación de la página web (Cross-site Scripting)
Fecha de publicación:
27/03/2026
Última modificación:
31/03/2026

Descripción

*** Pendiente de traducción *** Handlebars provides the power necessary to let users build semantic templates. In versions 4.0.0 through 4.7.8, the Handlebars CLI precompiler (`bin/handlebars` / `lib/precompiler.js`) concatenates user-controlled strings — template file names and several CLI options — directly into the JavaScript it emits, without any escaping or sanitization. An attacker who can influence template filenames or CLI arguments can inject arbitrary JavaScript that executes when the generated bundle is loaded in Node.js or a browser. Version 4.7.9 fixes the issue. Some workarounds are available. First, validate all CLI inputs before invoking the precompiler. Reject filenames and option values that contain characters with JavaScript string-escaping significance (`"`, `'`, `;`, etc.). Second, use a fixed, trusted namespace string passed via a configuration file rather than command-line arguments in automated pipelines. Third, run the precompiler in a sandboxed environment (container with no write access to sensitive paths) to limit the impact of successful exploitation. Fourth, audit template filenames in any repository or package that is consumed by an automated build pipeline.

Productos y versiones vulnerables

CPE Desde Hasta
cpe:2.3:a:handlebarsjs:handlebars:*:*:*:*:*:node.js:*:* 4.0.0 (incluyendo) 4.7.9 (excluyendo)