CVE-2026-25521

Estado: ModificadaCrítica (9.4)—

Locutus brings stdlibs of other programming languages to JavaScript for educational purposes. In versions from 2.0.12 to before 2.0.39, a prototype pollution vulnerability exists in locutus. Despite a previous fix that attempted to mitigate prototype pollution by checking whether user input contained a forbidden key, it is still possible to pollute Object.prototype via a crafted input using String.prototype. This issue has been patched in version 2.0.39.

CVSS

Versión: 4.0
Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Puntuación base: 9.4

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.50%
Percentil entre todas las CVEs puntuadas: 41
Fecha de la puntuación: 6/10/2026

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access60 %
Impacto principalT1059.007 JavaScriptexecution55 %

Inferido por reglas deterministas a partir del vector CVSS y la CWE. Solo orientativo.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Vulnerability Scanning Restrict Web-Based Content Privileged Account Management Network Segmentation Limit Access to Resource Over Network Filter Network Traffic

Tecnologías afectadas (1)

Locutus — Locutus

CWE

CWE-1321
CWE-915

Referencias

JSON original (NVD)

Mostrar

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      "value": "Locutus incorpora librerías estándar de otros lenguajes de programación a JavaScript con fines educativos. En las versiones desde la 2.0.12 hasta antes de la 2.0.39, existe una vulnerabilidad de contaminación de prototipos en Locutus. A pesar de una corrección anterior que intentó mitigar la contaminación de prototipos verificando si la entrada del usuario contenía una clave prohibida, todavía es posible contaminar Object.prototype mediante una entrada manipulada utilizando String.prototype. Este problema ha sido corregido en la versión 2.0.39."
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