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).

Concrete CMS versions 9 through 9.3.3 and versions below 8.5.19 are vulnerable to stored XSS in the calendar event addition feature because the calendar event name was not sanitized on output. Users or groups with permission to create event calendars can embed scripts, and users or groups with permission to modify event calendars can execute scripts. The Concrete CMS Security Team gave this vulnerability a CVSS v4 score of 4.6 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N Thank you, Yusuke Uchida for reporting. CNA updated this risk rank on 20 Jan 2025 by lowering the AC based on CVSS 4.0 documentation that access privileges should not be considered for AC)

Concrete CMS versions 9.0.0 through 9.3.3 are affected by a stored XSS vulnerability in the "Top Navigator Bar" block. Since the "Top Navigator Bar" output was not sufficiently sanitized, a rogue administrator could add a malicious payload that could be executed when targeted users visited the home page.The Concrete CMS Security Team gave this vulnerability a CVSS v4 score of 4.6 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N . This does not affect versions below 9.0.0 since they do not have the Top Navigator Bar Block. Thanks, Chu Quoc Khanh for reporting.

Concrete CMS versions 9.0.0 to 9.3.3 and below 8.5.19 are vulnerable to Stored XSS in the "Next&Previous Nav" block. A rogue administrator could add a malicious payload by executing it in the browsers of targeted users. The Concrete CMS Security Team gave this vulnerability a CVSS v4 score of 4.6 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N  Since the "Next&Previous Nav" block output was not sufficiently sanitized, the malicious payload could be executed in the browsers of targeted users. Thanks, Chu Quoc Khanh for reporting.

Concrete CMS versions 9.0.0 through 9.3.2 are affected by a stored XSS vulnerability in Board instances. A rogue administrator could inject malicious code. The Concrete CMS security team gave this vulnerability a CVSS 4.0 Score of 4.6 with vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Versions below 9 are not affected. Thanks, m3dium for reporting. (CNA updated AC score to L based on CVSS 4.0 documentation)

Concrete CMS versions 9.0.0 to 9.3.2 and below 8.5.18 are vulnerable to Stored XSS in RSS Displayer when user input is stored and later embedded into responses. A rogue administrator could inject malicious code into fields due to insufficient input validation. The Concrete CMS security team gave this vulnerability 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, m3dium 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)

Concrete CMS versions 9 through 9.3.2 and below 8.5.18 are vulnerable to Stored XSS in getAttributeSetName(). A rogue administrator could inject malicious code. The Concrete CMS team gave this a CVSS v4.0 rank of 4.6 with vector https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:N/AC:H/AT:N/PR:H/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks, m3dium for reporting. (CNA updated this risk rank on 20 Jan 2025 by lowering the AC based on CVSS 4.0 documentation that access privileges should not be considered for AC)

Concrete CMS versions 9.0.0 through 9.3.2 are affected by a stored XSS vulnerability in the generate dashboard board instance functionality. The Name input field does not check the input sufficiently letting a rogue administrator have the capability to inject malicious JavaScript code. The Concrete CMS security team gave this vulnerability a CVSS v4 score of 4.6 with a vector of CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N. Concrete versions below 9 are not affected by this vulnerability.Thanks fhAnso 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).