CVE-2026-52841 Easy!Appointments: Authorization bypass in Google OAuth provider binding lets any backend user rebind a peer provider's Google sync
Logged-in users can rebind other users' Google OAuth providers to their own accounts, gaining unauthorized access to peer appointment data.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-52841?
CVE-2026-52841 is a low-severity missing authorization vulnerability in alextselegidis easyappointments, published on 14 Jul 2026. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Official description
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.
Weakness: CWE-639
Which versions are affected by CVE-2026-52841?
2 open source packages ship an affected version, including alextselegidis/easyappointments.
| Package | Affected | Fixed in |
|---|---|---|
alextselegidis/easyappointments Packagist | All versions to 1.5.2 | None |
alextselegidis/easyappointments Packagist | All versions to 1.5.2 | None |
How do I fix CVE-2026-52841?
No fix has been published for CVE-2026-52841 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-52841 being exploited?
There is no known exploitation of CVE-2026-52841 in the wild and no public exploit code.
Sources
Also known as GHSA-8hm4-r66f-29wr.