CoolClock permits contributor stored XSS in HTML attributes
CoolClock before 4.3.8 outputs an attacker-controlled skin setting inside an HTML attribute without adequate escaping. A Contributor or higher role can store script-bearing markup that executes when the affected content is viewed. The authoritative export does not name the setting, save action, or rendering function.
- Component
- CoolClock
- Plugin slug
coolclock- Affected
- < 4.3.8
- Safe version
4.3.8- Published
- Sep 11, 2026
This CVE was published Sep 11, 2026 and is one of 3 known issues for this plugin.
Update, patch or deactivate.
Update CoolClock to 4.3.8 or later. The authoritative export marks versions below 4.3.8 affected. The application-level fix must validate the skin setting when saved and apply attribute-context escaping when it is rendered.
A safe version is available, so updating to that version or later is the preferred remediation. If an immediate update is not practical, consider a targeted application patch or temporarily restricting the affected functionality.
Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.
Technical description
The CoolClock WordPress plugin before 4.3.8 does not properly escape a skin setting before outputting it within an HTML attribute, allowing users with contributor-level access and above to inject arbitrary web scripts that execute when the content is viewed.
CVE / CNA vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:H