CVE-2026-23478 — Cal.com has an Authentication Bypass via Unvalidated Email in Custom JWT Callback
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 authenticat…
Published: 2026-01-13 · CVSS: 10.0 · CVSS 4.0
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7