CVE-2026-84003

Estado: AnalizadaAlta (7.4)—

Authentication bypass by capture-replay in Microsoft Authentication Library (MSAL) for Node.js allows an unauthorized attacker to perform spoofing over a network.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Puntuación base: 7.4

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.60%
Percentil entre todas las CVEs puntuadas: 47
Fecha de la puntuación: 5/10/2026

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 access85 %
Impacto principalT1078.004 Cloud Accountsstealth · persistence · privilege escalation · initial access75 %
Impacto secundarioT1556.002 Password Filter DLLdefense impairment · persistence · credential access60 %

AV:N sin PR indica explotación remota sin privilegios (T1190). CWE-294 (captura-replay) permite bypass de autenticación en MSAL-Node, permitiendo suplantar identidades y comprometer cuentas (T1078.004) o modificar políticas de autenticación (T1556.002).

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Privileged Account Management Active Directory Configuration Vulnerability Scanning User Training User Account Management Password Policies

Tecnologías afectadas (1)

Microsoft — Azure/msal-node

CWE

CWE-294

Referencias

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-84003

JSON original (NVD)

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