CVE-2026-19804: s2Member (WordPress plugin) · Code Injection
Affects s2Member (WordPress plugin)Source CVE Database V5
Not known to be exploited · CVSS 8.8 High.
Data as of 9 Nov 2026, 23:24 UTC
- EPSS
- 1.0% chance of exploitation in 30 days – higher than 64% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 25 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 9 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| clavaques2Member – Excellent for All Kinds of Memberships, Content Restriction Paywalls & Member Access Subscriptions | Affected
| Fixed in– |
AI-suggested
Until a fix is available, site administrators should consider removing or disabling the Signup Tracking Codes template containing the %%first_name%% placeholder to prevent exploitation. Additionally, monitoring and restricting access to PayPal Checkout AJAX endpoints may reduce exposure of the proxy verification key. Follow vendor advisories closely for official patches or updates.
Description
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.
References
- wordfence.com/threat-intel/vulnerabilities/id/e87da8fa-04cc-4b9a-9dde-be7d4f2bd76e?source=cve (opens in a new tab)
- plugins.trac.wordpress.org/browser/s2member/trunk/src/includes/classes/utilities.inc.php (opens in a new tab)
- plugins.trac.wordpress.org/browser/s2member/trunk/src/includes/classes/tracking-codes.inc.php (opens in a new tab)
- plugins.trac.wordpress.org/browser/s2member/trunk/src/includes/classes/paypal-return-in-subscr-or-wa-w-level.inc.php (opens in a new tab)
- plugins.trac.wordpress.org/browser/s2member/trunk/src/includes/classes/paypal-return-in-subscr-or-wa-w-level.inc.php (opens in a new tab)
- plugins.trac.wordpress.org/browser/s2member/trunk/src/includes/classes/paypal-utilities.inc.php (opens in a new tab)
- plugins.trac.wordpress.org/browser/s2member/trunk/src/includes/classes/paypal-utilities.inc.php (opens in a new tab)
- plugins.trac.wordpress.org/browser/s2member/trunk/src/includes/classes/paypal-checkout-in.inc.php (opens in a new tab)
- plugins.trac.wordpress.org/browser/s2member/trunk/src/includes/classes/paypal-return-in.inc.php (opens in a new tab)
- plugins.trac.wordpress.org/changeset?reponame=&old=3671073%40s2member&new=3671073%40s2member (opens in a new tab)