Auth bypass in Alextselegidis Easyappointments

CVE-2026-52841

Easy!Appointments is a self hosted appointment scheduler. In versions prior to 1.6.0, `Google::oauth` at `application/controllers/Google.php:278` stores its URL-supplied `provider_id` in the session, and `oauth_callback` saves the issued Google OAuth token against that row without checking the caller owns the provider. Any logged-in backend user (admin, provider, or secretary) rebinds a peer provider's Google sync to a Google account they control. The peer's appointments then sync into the attacker's calendar with each customer's name and email attached as attendee data. Version 1.6.0 patches the issue.

Vulnerability class: IDOR (Insecure Direct Object Reference)

EPSS: 0.002 (10.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 3.1 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-52841?
CVE-2026-52841 is a low-severity vulnerability in Alextselegidis Easyappointments, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 3.1/10. Published 2026-07-14.
How severe is CVE-2026-52841?
Low severity. CVSS v3 base score is 3.1 out of 10.