YMC Filter < 3.12.8 - Contributor+ Stored XSS via Layout Builder Schema
Priority MEDIUM 58CWE-79Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Cross-site scripting
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-79.
Summary
The YMC Filter WordPress plugin before 3.12.8 does not sanitize and escape a layout builder setting before outputting it on a public endpoint, and does not verify object ownership when the setting is saved, allowing users with the Contributor role and above to store JavaScript that executes in the browser of any visitor viewing an affected filter.
Why it matters now
Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00226 13th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by the CNA
Fix Fixed YMC Filter (Unknown): 3.12.8
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- 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 |
|---|---|---|---|---|---|
| Unknown | YMC Filter | 3.6.0 to before 3.12.8 | 3.12.8 | Patch available | CNA |
- YMC Filter VendorUnknown Affected 3.6.0 to before 3.12.8 Fixed in 3.12.8 Patch available CNA
Remediation
- Fix · CNA YMC Filter (Unknown) Fixed in 3.12.8
Timeline
- 2026-10-02 Threatist record created from CVE-2026-16558
- 2026-10-03 Alias added: GHSA-p3q7-6w8f-v63h
References
Sources
- CVE-2026-16558 · CVE Program
- CVE-2026-16558 · NVD
- FIRST EPSS
- GHSA-p3q7-6w8f-v63h · 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