CVE-2026-23478

critical · 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

0.5%

EPSS (exploit prob.)

39th

EPSS percentile

2026-01-13

Published

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

Weaknesses

CWE-602CWE-639

Affected products

Vendor	Product	Affected versions
cal	cal.com	>= 3.1.6, < 6.0.7

Check a specific version with /api/v1/cve/match.

References

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

Query this programmatically:

curl https://evil-db.io/api/v1/cve/CVE-2026-23478