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

03 Feb 2026, 19:29

Type	Values Removed	Values Added
CPE		cpe:2.3:a:cal:cal.com::::::::
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

Information

Published : 2026-01-13 22:16

Updated : 2026-02-03 19:29

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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