Quick answers
- Is CVE-2026-116866 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-116866 being exploited in the wild.
- How severe is CVE-2026-116866?
- High severity, with a CVSS score of 8.8, published 29 October 2026.
- Which products and versions are affected?
- WooCommerce Extra Fees Plugin for WooCommerce through 4.4.0.
- Is there a fix for CVE-2026-116866?
- No fixed version is recorded yet. Patchstack has issued a mitigation rule to block attacks until an official patch is available. As an immediate action, contact your hosting provider or web developer to remove or disable the plugin until a patch is released. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-116866 attacked?
- It is attacked over the network, in a web application.
- Am I affected by CVE-2026-116866?
- Check whether you run WooCommerce Extra Fees Plugin for WooCommerce at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
Patchstack has issued a mitigation rule to block attacks until an official patch is available. As an immediate action, contact your hosting provider or web developer to remove or disable the plugin until a patch is released.
Technical details
The vulnerability is a PHP object injection flaw in versions up to 4.4.0 that can be exploited by an authenticated contributor-level user. Object injection allows manipulation of serialized data to instantiate and invoke arbitrary PHP objects, leading to remote code execution on the server. No official patch is currently available.
Affected products
- WooCommerce Extra Fees Plugin for WooCommerce through 4.4.0
Timeline
- 2026-10-29: disclosed
- 2026-09-17: other: Vulnerability reported by Patchstack