clavaque s2Member Plugin up to 261011 on WordPress shortcode wp_kses_post date_format cross site scripting

Summaryinfo

A vulnerability classified as problematic has been found in clavaque s2Member Plugin up to 261011. The affected element is the function wp_kses_post of the component shortcode Handler. This manipulation of the argument date_format causes cross site scripting. This vulnerability is handled as CVE-2026-109972. The attack can be initiated remotely. There is not any exploit available. Applying a patch is the recommended action to fix this issue.

Detailsinfo

A vulnerability was found in clavaque s2Member Plugin up to 261011. It has been declared as problematic. Affected by this vulnerability is the function wp_kses_post of the component shortcode Handler. The manipulation of the argument date_format with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. As an impact it is known to affect integrity. The summary by CVE is:

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.

The advisory is shared at wordfence.com. This vulnerability is known as CVE-2026-109972 since 10/13/2026. The exploitation appears to be easy. The attack can be launched remotely. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

Applying the patch 261011 is able to eliminate this problem.

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Productinfo

Type

• WordPress Plugin

Vendor

• clavaque

Name

• s2Member Plugin

Version

• 261011

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

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If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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