Extra Fees for WooCommerce <= 4.4.0 - Authenticated (Contributor+) PHP Object Injection via Fee Rule Post Meta

High 8.8 CWE-502Fixed in 4.4.1
ID
WPSEC-2026-2970
Plugin
Extra Fees for WooCommerce (woo-conditional-product-fees-for-checkout)
Affected
all versions before 4.4.1
Remediation
Update to 4.4.1 or later.
CVSS 3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness
CWE-502
Usage
Plugin Low · Affected versions Low among sites WPSec scans, 2026-11-12
Attack surface
Extra Fees for WooCommerce on WPSec AttackSurface
Fix released
Published

Also published later by Wordfence as CVE-2026-116866, on 2026-10-28.

Description

The Extra Fees for WooCommerce plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 4.4.0 via deserialization of fee rule post meta (such as 'cost_rule_match', 'product_fees_metabox' and 'ds_select_day_of_week') with maybe_unserialize(). The fee custom post type was registered without capability restrictions and its meta keys were not protected, so low-privileged users could write serialized payloads into fee meta, for example via XML-RPC custom fields. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject a PHP Object. No known POP chain is present in the vulnerable software itself; if a POP chain is present via an additional plugin or theme installed on the target system, it may allow the attacker to delete arbitrary files, retrieve sensitive data, or execute code.

References

Published by WPSec. Provided as is, without warranty. Corrections: contact us.

This advisory as JSON or Markdown · All advisories: JSON, RSS

License: CC BY 4.0