ZeM STL <= 1.0 - Authenticated (Contributor+) Stored Cross-Site Scripting via Shortcode Attributes
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- 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 ZeM STL plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the [zemstl] shortcode in all versions up to and including 1.0. This is due to insufficient input sanitization and output escaping on user-supplied shortcode attributes, specifically the 'url', 'color', and 'bgcolor' parameters. These attribute values are directly interpolated into HTML attribute context without being passed through esc_attr() or any other escaping function. 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.
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-2026-4081
- 2026-10-03 Alias added: GHSA-x84m-mwh2-95qm
References
Other 9
- https://www.wordfence.com/threat-intel/vulnerabilities/id/07e415f9-42f1-4c80-a023-38f460f634d3?source=cve
- https://plugins.trac.wordpress.org/browser/zem-stl-viewer/trunk/zemstl.php#L107
- https://plugins.trac.wordpress.org/browser/zem-stl-viewer/tags/1.0/zemstl.php#L107
- https://plugins.trac.wordpress.org/browser/zem-stl-viewer/trunk/zemstl.php#L74
- https://plugins.trac.wordpress.org/browser/zem-stl-viewer/tags/1.0/zemstl.php#L74
- https://plugins.trac.wordpress.org/browser/zem-stl-viewer/trunk/zemstl.php#L103
- https://plugins.trac.wordpress.org/browser/zem-stl-viewer/tags/1.0/zemstl.php#L103
- https://plugins.trac.wordpress.org/browser/zem-stl-viewer/trunk/zemstl.php#L104
- https://plugins.trac.wordpress.org/browser/zem-stl-viewer/tags/1.0/zemstl.php#L104
Sources
- CVE-2026-4081 · CVE Program
- CVE-2026-4081 · NVD
- FIRST EPSS
- GHSA-x84m-mwh2-95qm · 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