CVE-2026-109972
Description
The s2Member – Excellent for All Kinds of Memberships, Content Restriction Paywalls & Member Access Subscriptions plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'date_format' parameter in all versions up to, and including, <= 261011 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The payload bypasses wp_kses_post() on save because it contains no literal angle brackets — only backslash-escaped sequences that PHP's date() materializes into HTML tag characters at render time after WordPress's shortcode_parse_atts() applies stripcslashes() to the attribute value.
References
- https://plugins.trac.wordpress.org/browser/s2member/trunk/src/includes/classes/sc-gets-in.inc.php#L119
- https://plugins.trac.wordpress.org/browser/s2member/trunk/src/includes/classes/sc-gets-in.inc.php#L53
- https://plugins.trac.wordpress.org/browser/s2member/trunk/src/includes/classes/sc-gets-in.inc.php#L98
- https://plugins.trac.wordpress.org/browser/s2member/trunk/src/includes/codes.inc.php#L24
- https://plugins.trac.wordpress.org/changeset/3751344/s2member/trunk/src/includes/classes/sc-gets-in.inc.php