# CVE-2026-52839: Easy!Appointments authorization bypass in appointment store and update

Source: https://junglewise.ai/threats/cve-2026-52839-easy-appointments-authorization-bypass-in-appointment-store-and  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-14. Updated: 2026-07-29  
License: CC BY 4.0 with a link back

CVE-2026-52839 · Severity: low · CVSS 3.3 · Published 2026-07-14

Easy!Appointments is an open-source appointment scheduling system. A security flaw allows an authenticated staff member (provider) to create or modify appointments for other staff members, which should normally be restricted. This could lead to scheduling disruptions, such as unauthorized double-bookings or staff members hiding their own appointments by moving them to a colleague's calendar.

Technologies: [alextselegidis/easyappointments (Packagist)](https://junglewise.ai/threats/technologies/alextselegidis-easyappointments). Vendors: [Packagist](https://junglewise.ai/threats/vendors/packagist).

## Quick answers

**Is CVE-2026-52839 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-52839 being exploited in the wild.

**How severe is CVE-2026-52839?** Low severity, with a CVSS score of 3.3, published 14 July 2026.

**Which products and versions are affected?** alextselegidis/easyappointments (Packagist) <= 1.5.2, ECOSYSTEM:introduced=0,fixed=1.6.0.

**Is there a fix for CVE-2026-52839?** Yes. alextselegidis/easyappointments (Packagist): upgrade to 1.6.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-52839 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-52839?** Check whether you run alextselegidis/easyappointments (Packagist) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- alextselegidis/easyappointments (Packagist): upgrade to 1.6.0 or later

  ```sh
  composer require alextselegidis/easyappointments:^1.6.0
  ```


## Technical details

The vulnerability exists in the `appointments/store` and `appointments/update` endpoints of Easy!Appointments. While the application correctly filters search results by provider, these mutation endpoints only verify generic 'add' or 'edit' permissions and fail to validate that the `id_users_provider` field matches the authenticated user's session. An attacker with provider-level privileges can submit a crafted JSON payload to inject new appointments into another provider's schedule or reassign existing ones. Additionally, the `store` endpoint contains a 'write-before-crash' bug where the unauthorized record is committed to the database before a type error causes a 500 response, potentially masking the successful exploit. The issue is fixed in version 1.6.0.

## Affected products

- alextselegidis Easy!Appointments <= 1.5.2

## Identifiers

- CVE-2026-52839
- GHSA-w8xc-8g92-v77h

## Timeline

- 2026-05-25: disclosed: Vulnerability reported by Yash Shendge
- 2026-06-15: patched: Version 1.6.0 released
- 2026-07-14: advisory: NVD publication date
- 2026-07-29: advisory: GitHub Advisory published

## References

- [https://api.github.com/users/ashrexon](https://api.github.com/users/ashrexon)
- [https://github.com/ashrexon](https://github.com/ashrexon)
- [https://api.github.com/users/ashrexon/gists%7B/gist_id%7D](https://api.github.com/users/ashrexon/gists%7B/gist_id%7D)
- [https://api.github.com/users/ashrexon/repos](https://api.github.com/users/ashrexon/repos)
- [https://avatars.githubusercontent.com/u/75063323?v=4](https://avatars.githubusercontent.com/u/75063323?v=4)
- [https://api.github.com/users/ashrexon/events%7B/privacy%7D](https://api.github.com/users/ashrexon/events%7B/privacy%7D)

## Related threats

- [Easy!Appointments excessive data exposure in customer search](https://junglewise.ai/threats/cve-2026-55651-easy-appointments-excessive-data-exposure-in-customer-search)
- [Easy!Appointments authorization bypass in Google OAuth provider binding](https://junglewise.ai/threats/cve-2026-52841-easy-appointments-authorization-bypass-in-google-oauth-provider)
- [alextselegidis Easy!Appointments SSRF in CalDAV connection test](https://junglewise.ai/threats/cve-2026-52840-alextselegidis-easy-appointments-ssrf-in-caldav-connection-test)
- [Easy!Appointments stored XSS in booking disabled message](https://junglewise.ai/threats/cve-2026-52838-easy-appointments-stored-xss-in-booking-disabled-message)
- [alextselegidis Easy!Appointments information disclosure in reschedule view](https://junglewise.ai/threats/cve-2026-52837-alextselegidis-easy-appointments-information-disclosure-in)