CVE-2026-8353 (GCVE-0-2026-8353)

Vulnerability from cvelistv5 – Published: 2026-05-22 14:18 – Updated: 2026-05-22 17:08
VLAI
Title
Concrete CMS version 9.0 to 9.5.0 is vulnerable to Stored XSS via page name in atomik theme
Summary
Concrete CMS version 9.0 to 9.5.0 is vulnerable to Stored XSS via page name in the Atomik theme. A rogue editor can inject arbitrary JavaScript that executes in the context of any authenticated user visiting the affected account pages. This can lead to session hijacking, credential theft, malicious actions performed on behalf of users, and potential privilege escalation. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 2.1 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori (Tenzai) for reporting.
Severity
2.1 (Low)
CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-22 17:05 UTC
CWE
  • CWE-79 - Improper neutralization of input during web page generation ('cross-site scripting')
Assigner
ConcreteCMS CNA under the mitre root
CNA scorecard B 84/100 over 111 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Concrete CMS Concrete CMS Affected: 9.0 , ≤ 9.5.0 (git)
guessed Create a notification for this product.
Credits
Yonatan Drori (Tenzai)
Show details on NVD website
To clipboard 

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    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.