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

CVE-2026-33937

Gravedad CVSS v3.1:
CRÍTICA
Tipo:
CWE-94 Control incorrecto de generación de código (Inyección de código)
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, `Handlebars.compile()` accepts a pre-parsed AST object in addition to a template string. The `value` field of a `NumberLiteral` AST node is emitted directly into the generated JavaScript without quoting or sanitization. An attacker who can supply a crafted AST to `compile()` can therefore inject and execute arbitrary JavaScript, leading to Remote Code Execution on the server. Version 4.7.9 fixes the issue. Some workarounds are available. Validate input type before calling `Handlebars.compile()`; ensure the argument is always a `string`, never a plain object or JSON-deserialized value. Use the Handlebars runtime-only build (`handlebars/runtime`) on the server if templates are pre-compiled at build time; `compile()` will be unavailable.

Productos y versiones vulnerables

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