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CVE-2026-81899 (GCVE-0-2026-81899)

Vulnerability from cvelistv5 – Published: 2026-09-15 17:54 – Updated: 2026-09-15 19:18
VLAI
Title
Concrete CMS 9.0 to 9.5.2 is vulnerable to Stored XSS via group folder name on the Members > Groups dashboard
Summary
Concrete CMS 9.0.0 to 9.5.2 stored group folder names without sanitization and printed them unescaped on the Members > Groups dashboard page, resulting in stored cross-site scripting. The add and edit group-folder handlers stored the submitted folder name without neutralizing HTML, and the group search grid returned it without output encoding, so the Groups dashboard rendered the name as live markup. An authenticated user holding the Add Group Folder permission could store a script payload as a folder name that executed in the session of any administrator who viewed the Groups dashboard, enabling session and token theft and any action available in the administrator's context. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 7.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N. Thanks Lý Chấn Hưng (hunglyvn) for reporting.
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-15 19:18 UTC
CWE
  • CWE-79 - Improper neutralization of input during web page generation ('cross-site scripting')
References
Impacted products
Vendor Product Version CPE status
Concrete CMS Concrete CMS Affected: 9.0.0 , ≤ 9.5.2 (git)
guessed Create a notification for this product.
Credits
Show details on NVD website

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