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TI-2026-56507 Aliases CVE-2026-81896GHSA-jhq2-9mcm-q56w

Cross-site scripting in Concrete CMS

Priority LOW 38CWE-79Published · Updated

Key facts

Attack vector
Network
Privileges required
High
User interaction
Passive
Attack complexity
Low
Attack requirements
None
Impact type
Cross-site scripting
Confidentiality · integrity · availability
High · High · None
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-79.

Summary

Concrete CMS before 9.5.3 does not apply HTML entity encoding to user-defined Form block question labels when rendering them as column headers in the Dashboard Form Submissions report (concrete/single_pages/dashboard/reports/forms/legacy.php). a rogue editor could store markup or script in a label that then executes in the browser of any administrator who opens the submissions report for the affected form, producing stored cross-site scripting in the Dashboard. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 8.4 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori from Tenzai for reporting.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00237 14th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

No affected products listed by the sources yet.

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:concretecms:concrete_cms:*:*:*:*:*:*:*:*before 9.5.3VulnerableConcrete CMS
  • cpe:2.3:a:concretecms:concrete_cms:*:*:*:*:*:*:*:* Versions before 9.5.3 Vulnerable ·Concrete CMS

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-81896
  2. 2026-10-03 Alias added: GHSA-jhq2-9mcm-q56w

References

  • TI-2026-23602 ConcreteCMS v9.4.7 contains a Denial of Service (DoS) vulnerability in the File Manager… CVSS 3.1MEDIUM 6.5
  • TI-2023-23992 A Cross Site Scripting (XSS) vulnerability in Concrete CMS from versions 9.2.0 to 9.2.2… CVSS 3.1MEDIUM 5.4
  • TI-2023-26495 Concrete CMS before 8.5.13 and 9.x before 9.2.2 allows unauthorized access because… CVSS 3.1CRITICAL 9.8
  • TI-2026-14907 Missing authorization in Concrete CMS CVSS 4.0HIGH 8.7
  • TI-2022-06200 Cleartext transmission of sensitive information in https://github.com/concrete5/concrete5 CVSS 3.1CRITICAL 9.8
  • TI-2021-17294 An issue was discovered in Concrete CMS through 8.5.5. CVSS 3.1CRITICAL 9.8
See all 197 →

Sources