Stored cross-site scripting in CMB2 WordPress plugin fields
Key facts
- Attack vector
- Network
- Privileges required
- None
- 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 CMB2 plugin for WordPress up to and including 2.13.4 has a stored cross-site scripting flaw (CWE-79). Insufficient input sanitization and output escaping let unauthenticated attackers inject web scripts into pages that run when a user opens the injected page. It only applies when a site integrator places a wysiwyg field inside a repeatable group on a public front-end form.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
Description from the CNA
The CMB2 plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'cmb43ex1_grp[0][txt] (wysiwyg field inside group — field id controlled by integrator config)' parameter in all versions up to, and including, 2.13.4 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This is only exploitable when a site integrator renders the plugin's documented front-end form helper with a wysiwyg field inside a repeatable group on a publicly accessible 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 |
|---|---|---|---|---|---|
| jtsternberg | CMB2 | up to 2.13.4 | — | No fix listed | CNA |
- CMB2 Vendorjtsternberg Affected up to 2.13.4 Fixed in — No fix listed CNA
Remediation
The sources list no fixed version for CMB2.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
Timeline
- 2026-10-28 Threatist record created from CVE-2026-116761
- 2026-10-28 Alias added: GHSA-rfx8-wq2m-j436
- 2026-10-28 Priority changed: MEDIUM → LOW
- 2026-10-29 CISA SSVC decision points changed
References
Other 7
- https://www.wordfence.com/threat-intel/vulnerabilities/id/97215367-08c0-46cc-a595-4475274a5a1c?source=cve
- https://plugins.trac.wordpress.org/browser/cmb2/tags/2.13.4/includes/CMB2_Field.php#L715
- https://plugins.trac.wordpress.org/browser/cmb2/tags/2.13.4/includes/types/CMB2_Type_Wysiwyg.php#L93
- https://plugins.trac.wordpress.org/browser/cmb2/tags/2.13.4/includes/helper-functions.php#L320
- https://plugins.trac.wordpress.org/browser/cmb2/tags/2.13.4/includes/CMB2_Sanitize.php#L447
- https://github.com/CMB2/CMB2/commit/fbeb7c4688dc5b8635a34978d837f1d458dcac44
- https://plugins.trac.wordpress.org/changeset/3767609/cmb2/trunk/includes/CMB2_Field.php
More jtsternberg vulnerabilities
- TI-2024-01668 CMB2 <= 2.10.1 - Authenticated (Contributor+) PHP Object Injection CVSS 3.1HIGH 7.5
- TI-2026-66010 CMB2 <= 2.13.1 - Unauthenticated Stored Cross-Site Scripting via 'textarea_code' Field CVSS 3.1HIGH 7.2
- TI-2026-65993 CMB2 <= 2.13.0 - Unauthenticated Stored Cross-Site Scripting via 'file_list' Field Type CVSS 3.1HIGH 7.2
- TI-2024-12915 Code Snippets CPT <= 2.1.0 - Authenticated (Subscriber+) Arbitrary Shortcode Execution CVSS 3.1MEDIUM 6.3
Sources
- CVE-2026-116761 · CVE Program
- CVE-2026-116761 · NVD
- FIRST EPSS
- GHSA-rfx8-wq2m-j436 · 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