Cross-site scripting in SherkSpear Sherk Custom Post Type Displays
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 Sherk Custom Post Type Displays plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'title' shortcode attribute in all versions up to, and including, 1.2.1. This is due to insufficient input sanitization and output escaping on the 'title' attribute of the 'sherkcptdisplays' shortcode. Specifically, in the sherkcptdisplays_func() function in includes/SherkCPTDisplaysShortcode.php, the 'title' attribute value is extracted from shortcode_atts() on line 19 and directly concatenated into an HTML <h2> tag on line 31 without any 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.
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
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| SherkSpear | Sherk Custom Post Type Displays | up to 1.2.1 | — | No fix listed | CNA |
- Sherk Custom Post Type Displays VendorSherkSpear Affected up to 1.2.1 Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2026-3554
- 2026-10-03 Alias added: GHSA-x8x7-xgj7-47r4
References
Other 5
- https://www.wordfence.com/threat-intel/vulnerabilities/id/d227d4e4-2899-434c-8b93-8d93a89b1b1b?source=cve
- https://plugins.trac.wordpress.org/browser/sherk-custom-post-type-displays/trunk/includes/SherkCPTDisplaysShortcode.php#L31
- https://plugins.trac.wordpress.org/browser/sherk-custom-post-type-displays/tags/1.2.1/includes/SherkCPTDisplaysShortcode.php#L31
- https://plugins.trac.wordpress.org/browser/sherk-custom-post-type-displays/trunk/includes/SherkCPTDisplaysShortcode.php#L19
- https://plugins.trac.wordpress.org/browser/sherk-custom-post-type-displays/tags/1.2.1/includes/SherkCPTDisplaysShortcode.php#L19
More SherkSpear vulnerabilities
- TI-2024-34727 WordPress Add Ribbon Shortcode plugin <= 1.0.1 - Cross Site Scripting (XSS) vulnerability CVSS 3.1MEDIUM 6.5
Sources
- CVE-2026-3554 · CVE Program
- CVE-2026-3554 · NVD
- FIRST EPSS
- GHSA-x8x7-xgj7-47r4 · 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