Auth bypass in Cal Cal.com
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 ad…
EPSS: 0.004 (31.9th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Cal Cal.com
- Calcom Cal.com — versions >= 3.1.6, < 6.0.7
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Third Party Advisory)
Frequently asked questions
- What is CVE-2026-23478?
- CVE-2026-23478 is a critical-severity vulnerability in Cal Cal.com, classified under CWE-602. CVSS score: 9.8/10. Published 2026-01-13.
- How severe is CVE-2026-23478?
- Critical severity. CVSS v3 base score is 9.8 out of 10.