CVE-2026-23478

Estado: AnalizadaCrítica (10)—

Cal.com is open-source scheduling software. From 3.1.6 to before 6.0.7, there is a vulnerability in a custom NextAuth JWT callback that allows attackers to gain full authenticated access to any user's account by supplying a target email address via session.update(). This vulnerability is fixed in 6.0.7.

CVSS

Versión: 4.0
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:L/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: 10

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.46%
Percentil entre todas las CVEs puntuadas: 38
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 access90 %
Impacto secundarioT1556.001 Domain Controller Authenticationdefense impairment · persistence · credential access75 %

Acceso remoto sin autenticación (AV:N/PR:N/UI:N) a servidor web expuesto. Falla en JWT callback permite sesiones falsas: T1078.004 (OAuth/cuenta válida) e impersonación (T1556.001) de cualquier usuario con solo email.

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 User Training Multi-factor Authentication Active Directory Configuration Vulnerability Scanning User Account Management

Tecnologías afectadas (1)

CAL — Cal.com

CWE

CWE-602, CWE-639

Referencias

https://github.com/calcom/cal.com/security/advisories/GHSA-7hg4-x4pr-3hrg

JSON original (NVD)

Mostrar

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