Concrete CMS versions 9.0.0 to 9.3.3 and below 8.5.19 are vulnerable to Stored XSS in Image Editor Background Color.  A rogue admin could add malicious code to the Thumbnails/Add-Type. The Concrete CMS Security Team gave this a CVSS v4 score of 5.1 with vector https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:N/AC:H/AT:N/PR:H/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks,  Alexey Solovyev for reporting. (CNA updated this risk rank on 17 Jan 2025 by lowering the AC based on CVSS 4.0 documentation that access privileges should not be considered for AC).

Cross site scripting in Concrete CMS