websoudan MW WP Form Plugin up to 5.1.3 on WordPress update_post_meta memo cross site scripting

Summaryinfo

A vulnerability, which was classified as problematic, has been found in websoudan MW WP Form Plugin up to 5.1.3 on WordPress. Impacted is the function update_post_meta. The manipulation of the argument memo leads to cross site scripting. This vulnerability is listed as CVE-2026-8853. The attack may be initiated remotely. There is no available exploit. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in websoudan MW WP Form Plugin up to 5.1.3 on WordPress. It has been rated as problematic. This issue affects the function update_post_meta. The manipulation of the argument memo with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to 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. Impacted is integrity. The summary by CVE is:

The MW WP Form plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'memo' parameter in all versions up to, and including, 5.1.3 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with editor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. Because the memo value is stored via update_post_meta() rather than wp_insert_post(), WordPress's built-in kses and unfiltered_html protections do not apply, allowing attackers to break out of the textarea element via injected closing tags regardless of role-based content filtering.

The weakness was presented by Sérgio Charruadas. The advisory is shared at wordfence.com. The identification of this vulnerability is CVE-2026-8853 since 05/18/2026. The exploitation is known to be easy. The attack may be initiated remotely. Additional levels of successful authentication are necessary for exploitation. 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.

Upgrading to version 5.1.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-35995). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• WordPress Plugin

Vendor

• websoudan

Name

• MW WP Form Plugin

Version

• 5.1.0
• 5.1.1
• 5.1.2
• 5.1.3

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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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