CVE-2026-66565: WordPress FC United theme <= 1.1.1 - PHP Object Injection vulnerability

Q: Who can exploit this issue?

The issue is unauthenticated, so an attacker does not need a WordPress account or prior access to target an affected site.

Q: Which installations are affected?

WordPress sites using the FC United theme version 1.1.1 or earlier are affected according to the available information.

Q: What is the potential impact?

The vulnerability is rated critical with network access, low attack complexity, no required privileges or user interaction, and high impacts to confidentiality, integrity, and availability.

Published Oct 10, 2026

Updated

Unauthenticated PHP Object Injection in FC United <= 1.1.1 versions.

Affected Software

1 affected component

WordPress FC United<=1.1.1

Event History

Oct 10, 2026

CVE Published

via MITRE·07:36 PM

Data Sourced

via MITRE·07:36 PM

DescriptionSeverityWeakness

Data Sourced

via NVD·08:16 PM

DescriptionSeverityWeakness

Frequently Asked Questions

Who can exploit this issue?

The issue is unauthenticated, so an attacker does not need a WordPress account or prior access to target an affected site.

Which installations are affected?

WordPress sites using the FC United theme version 1.1.1 or earlier are affected according to the available information.

What is the potential impact?

The vulnerability is rated critical with network access, low attack complexity, no required privileges or user interaction, and high impacts to confidentiality, integrity, and availability.

Company

Resources

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co

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