Remote Code Execution Vulnerability in s2Member Plugin for WordPress
CVE-2026-19804

8.8HIGH

Key Information:

Vendor

WordPress
Status
S2member – Excellent For All Kinds Of Memberships, Content Restriction Paywalls & Member Access Subscriptions
Vendor
CVE Published:
25 September 2026

What is CVE-2026-19804?

The s2Member plugin for WordPress is susceptible to a remote code execution vulnerability. This issue arises from inadequate sanitization of the 'first_name' parameter, which results in the potential execution of malicious code on the server. The vulnerability is compounded by the exposure of the site-global proxy verification key in plaintext during PayPal Checkout AJAX requests, allowing attackers to bypass postback verifications. Exploiting this vulnerability requires the site administrator to have configured a Signup Tracking Codes template with the %%first_name%% placeholder, enabling unauthorized individuals to execute commands remotely, thus compromising the server's integrity.

Affected Version(s)

s2Member – Excellent for All Kinds of Memberships, Content Restriction Paywalls & Member Access Subscriptions 0 <= 260814

References

https://www.wordfence.com/threat-intel/vulnerabilities/id...
https://plugins.trac.wordpress.org/browser/s2member/trunk...
https://plugins.trac.wordpress.org/browser/s2member/trunk...

CVSS V3.1

Score:
8.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Supakiad S. (m3ez)
.