CVE-2026-83545

CoolClock < 4.3.8 - Contributor+ Stored XSS via Custom Skin JSON

The CoolClock WordPress plugin before 4.3.8 does not properly escape a custom skin setting before outputting it inside an inline script, allowing users with contributor-level access and above to inject arbitrary JavaScript that executes when the content is viewed.

Affected

CoolClock

CVSS v3.1 CNA

6.8 MEDIUMCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:H

EPSS

0.43% chance of exploitation in the next 30 days, 36th percentile

Published

2026-09-11

Proof-of-concept exploits (1)

• https://wpscan.com/vulnerability/d331d834-08f7-46e2-859a-7b797213ad0b/

References

• CVE Record
• NVD entry