CVE-2017-20206: Appointments <= 2.2.1 - Unauthenticated PHP Object Injection

Published Oct 18, 2025
·
Updated

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 wpmudevappointments cookie. This allows unauthenticated attackers to inject a PHP Object. Attackers were actively exploiting this vulnerability with the WPTheme() class to create backdoors.

Affected Software

2 affected components
WPMU DEV Appointments<=2.2.1
wpmudev Appointments Wordpress<=2.2.1

Remediation

Patch Available

https://plugins.trac.wordpress.org/changeset/1733186/appointments

Event History

Oct 18, 2025
CVE Published
via MITRE·03:33 AM
Data Sourced
via MITRE·03:33 AM
DescriptionSeverityWeakness
Data Sourced
via NVD·04:15 AM
RemedyDescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2017-20206?

CVE-2017-20206 has been classified as a medium severity vulnerability.

2

How do I fix CVE-2017-20206?

To fix CVE-2017-20206, update the WPMU DEV Appointments plugin to version 2.2.2 or later.

3

What causes CVE-2017-20206?

CVE-2017-20206 is caused by PHP Object Injection due to deserialization of untrusted input from the `wpmudev_appointments` cookie.

4

Who is affected by CVE-2017-20206?

CVE-2017-20206 affects all installations of the WPMU DEV Appointments plugin versions up to and including 2.2.1.

5

Can CVE-2017-20206 be exploited remotely?

Yes, CVE-2017-20206 can be exploited remotely by unauthenticated attackers.

Company

Resources

Contact

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info@secalerts.co
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CVE-2017-20206 - Appointments <= 2.2.1 - Unauthenticated PHP Object Injection - SecAlerts