MW WP Form <= 5.1.3 - Authenticated (Editor+) Stored Cross-Site Scripting via 'memo' Parameter
Key facts
- Attack vector
- Network
- Privileges required
- High
- User interaction
- None
- Attack complexity
- High
- Impact type
- Cross-site scripting
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-79.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2026-8853
- 2026-10-03 Alias added: GHSA-xqph-m7fw-c4rf
References
Other 6
- https://www.wordfence.com/threat-intel/vulnerabilities/id/2a6dfdec-c1c6-4300-ab0a-9fd1c550d09f?source=cve
- https://plugins.trac.wordpress.org/browser/mw-wp-form/tags/5.1.3/templates/contact-data/detail.php#L77
- https://plugins.trac.wordpress.org/browser/mw-wp-form/tags/5.1.3/classes/controllers/class.contact-data.php#L134
- https://plugins.trac.wordpress.org/browser/mw-wp-form/tags/5.1.0/templates/contact-data/detail.php#L77
- https://plugins.trac.wordpress.org/browser/mw-wp-form/tags/5.1.0/classes/controllers/class.contact-data.php#L134
- https://plugins.trac.wordpress.org/changeset?old_path=mw-wp-form/tags/5.1.3&new_path=mw-wp-form/tags/5.1.4
More websoudan vulnerabilities
- TI-2023-06010 MW WP Form <= 5.0.3 - Improper Limitation of File Name to Unauthenticated Arbitrary File Deletion CVSS 3.1CRITICAL 9.8
- TI-2026-65982 Cross-site scripting in websoudan MW WP Form CVSS 3.1HIGH 7.2
- TI-2026-82365 Sensitive information exposure in MW WP Form post_id parameter CVSS 3.1MEDIUM 5.3
- TI-2026-05447 Authorization bypass in websoudan MW WP Form CVSS 3.1MEDIUM 5.3
- TI-2024-16321 WordPress MW WP Form Plugin <= 5.0.6 is vulnerable to Cross Site Scripting (XSS) CVSS 3.1MEDIUM 6.5
Sources
- CVE-2026-8853 · CVE Program
- CVE-2026-8853 · NVD
- FIRST EPSS
- GHSA-xqph-m7fw-c4rf · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences