CVE-2026-23478

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 v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/calcom/cal.com/security/advisories/GHSA-7hg4-x4pr-3hrg	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:cal:cal.com:*:*:*:*:*:*:*:*

History

17 Jun 2026, 10:21

Type	Values Removed	Values Added
Summary		(es) Cal.com es software de programación de código abierto. Desde la 3.1.6 hasta antes de la 6.0.7, existe una vulnerabilidad en una devolución de llamada JWT de NextAuth personalizada que permite a los atacantes obtener acceso autenticado completo a la cuenta de cualquier usuario al proporcionar una dirección de correo electrónico objetivo a través de session.update(). Esta vulnerabilidad está corregida en la 6.0.7.

03 Feb 2026, 19:29

Type	Values Removed	Values Added
References	~~() https://github.com/calcom/cal.com/security/advisories/GHSA-7hg4-x4pr-3hrg -~~	() https://github.com/calcom/cal.com/security/advisories/GHSA-7hg4-x4pr-3hrg - Third Party Advisory
First Time		Cal cal.com Cal
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.8
CPE		cpe:2.3:a:cal:cal.com::::::::

13 Jan 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-13 22:16

Updated : 2026-06-17 10:21

NVD link : CVE-2026-23478

Mitre link : CVE-2026-23478

CVE.ORG link : CVE-2026-23478

JSON object : View

Products Affected

cal

cal.com

CWE

CWE-602

Client-Side Enforcement of Server-Side Security

CWE-639

Authorization Bypass Through User-Controlled Key

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