Reported vulnerability
Woocommerce Custom Product Addons Pro <= 5.4.1 - Unauthenticated Remote Code Execution via Custom Pricing Formula
Published 23 Mar 2026
Updated 23 Mar 2026
CVE-2026-4001
Compare your installed software with the affected versions below. Follow the source’s remediation guidance and test an available update after taking a backup. A database entry describes a reported issue; it does not establish whether a particular website has been compromised.
Does this affect my version?
Check your installed version against this advisory. This compares the report’s version ranges and does not scan your website.
Wordfence advisory
critical · CVSS 9.8The Woocommerce Custom Product Addons Pro plugin for WordPress is vulnerable to Remote Code Execution in all versions up to, and including, 5.4.1 via the custom pricing formula eval() in the process_custom_formula() function within includes/process/price.php. This is due to insufficient sanitization and validation of user-submitted field values before passing them to PHP's eval() function. The sanitize_values() method strips HTML tags but does not escape single quotes or prevent PHP code injection. This makes it possible for unauthenticated attackers to execute arbitrary code on the server by submitting a crafted value to a WCPA text field configured with custom pricing formula (pricingType: "custom" with {this.value}).
Severity vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Woocommerce Custom Product Addons Pro
- Software
- plugin · woo-custom-product-addons-pro
- Affected versions
- Start version unspecified, through 5.4.1
- Fix availability
- Fix available
- Fixed versions
- 5.4.2
Recommended action
Update to version 5.4.2, or a newer patched version
Further references (1)
Data sources and licences
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CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE®). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy.
Read licence termsSource: Wordfence
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Get help with this issueQuestions about this vulnerability
Which versions of Woocommerce Custom Product Addons Pro are affected?
Wordfence lists these affected versions: Start version unspecified, through 5.4.1. Use the version checker above to compare your installed release with this report.
Is a fix available for Woocommerce Custom Product Addons Pro?
Wordfence reports a fix for this issue in Woocommerce Custom Product Addons Pro. It lists these fixed versions: 5.4.2. Back up your website and test the recommended update before applying it to your live site.
Where can I find my installed plugin version?
In WordPress, open Plugins > Installed Plugins and find the version shown beneath the plugin name.
Does an affected version mean my website has been hacked?
An affected version means the installed release matches a vulnerability described in this report. It does not show whether anyone has exploited it on your website. The checker compares version numbers with stored reports; it does not inspect your website.