CVE-2017-20206
Appointments <= 2.2.1 - Unauthenticated PHP Object Injection
- State
- Published
- Severity
- 9.8 Critical
- Published
- Oct 18, 2025
- Updated
- Apr 8, 2026
- Reserved
- Oct 17, 2025
Description
The Appointments plugin for WordPress is vulnerable to PHP Object Injection in versions up to, and including, 2.2.1 via deserialization of untrusted input from the `wpmudev_appointments` cookie. This allows unauthenticated attackers to inject a PHP Object. Attackers were actively exploiting this vulnerability with the WP_Theme() class to create backdoors.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 9.8 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | Wordfence |
Weaknesses
- CWE-502 Deserialization of Untrusted Data
Affected Products
| Product | Versions |
|---|---|
Appointmentswpmudev |
|
References
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