Reported vulnerability

s2Member <= 260814 - Unauthenticated Remote Code Execution via 'first_name' Parameter in PayPal Proxy Return

Q: Which versions of s2Member – Excellent for All Kinds of Memberships, Content Restriction Paywalls & Member Access Subscriptions are affected?

Wordfence lists these affected versions: Start version unspecified, through 260814. Use the version checker above to compare your installed release with this report.

Q: Is a fix available for s2Member – Excellent for All Kinds of Memberships, Content Restriction Paywalls & Member Access Subscriptions?

Wordfence reports a fix for this issue in s2Member – Excellent for All Kinds of Memberships, Content Restriction Paywalls & Member Access Subscriptions. It lists these fixed versions: 260829. Back up your website and test the recommended update before applying it to your live site.

Q: Where can I find my installed plugin version?

In WordPress, open Plugins > Installed Plugins and find the version shown beneath the plugin name.

Published 24 Sept 2026

Updated 25 Sept 2026

CVE-2026-19804

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

high · CVSS 8.8

The s2Member – Excellent for All Kinds of Memberships, Content Restriction Paywalls & Member Access Subscriptions plugin for WordPress is vulnerable to Remote Code Execution in all versions up to, and including, 260814 via the 'first_name' parameter parameter. This is due to insufficient sanitization of the first_name parameter via esc_refs(), which strips only regex backreferences and not PHP tags, before substitution into the eval'd Signup Tracking Codes template, combined with disclosure of the site-global proxy verification key that allows PayPal postback verification to be bypassed. This makes it possible for unauthenticated attackers to execute code on the server. Successful exploitation requires that the site administrator has configured a Signup Tracking Codes template containing the %%first_name%% placeholder (a documented, GUI-supported feature) and that the attacker has obtained the site-global proxy verification key, which is exposed in plaintext in the JSON response of any PayPal Checkout AJAX request on the target site.

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

s2Member – Excellent for All Kinds of Memberships, Content Restriction Paywalls & Member Access Subscriptions

Software: plugin · s2member
Affected versions: Start version unspecified, through 260814
Fix availability: Fix available
Fixed versions: 260829

Recommended action

Update to version 260829, or a newer patched version

Further references (1)

wordfence.com/threat-intel/vulnerabilities/id/e87da8fa-04cc-4b9a-9dde-be7d4f2bd76e?source=api-prod

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.

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Source: Wordfence

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Questions about this vulnerability

Which versions of s2Member – Excellent for All Kinds of Memberships, Content Restriction Paywalls & Member Access Subscriptions are affected?

Wordfence lists these affected versions: Start version unspecified, through 260814. Use the version checker above to compare your installed release with this report.

Is a fix available for s2Member – Excellent for All Kinds of Memberships, Content Restriction Paywalls & Member Access Subscriptions?

Wordfence reports a fix for this issue in s2Member – Excellent for All Kinds of Memberships, Content Restriction Paywalls & Member Access Subscriptions. It lists these fixed versions: 260829. 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.

These reports cover at least one of the same plugins, themes or WordPress core. Check each report’s affected versions separately.

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