CVE-2017-20206

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.

CVSS v3.1 Score

9.8

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-502 Deserialization of Untrusted Data

Affected Products

Vendor	Product	Versions
wpmudev	appointments	< 2.2.1

References

Advisories & Patches

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

Other References

https://www.wordfence.com/blog/2017/10/3-zero-day-plugin-vulnerabilities-exploited-wild/ https://www.wordfence.com/threat-intel/vulnerabilities/id/7e8f230e-3f96-4efd-806d-72725b960303?source=cve

Frequently Asked Questions

What is CVE-2017-20206? +

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. It has a CVSS v3.1 base score of 9.8 (CRITICAL).

How severe is CVE-2017-20206? +

CVE-2017-20206 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2017-20206? +

CVE-2017-20206 affects products from wpmudev, specifically: appointments. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2017-20206? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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