CVE-2026-8139 LOW

CVE-2026-8139: Concrete CMS 9.5.0 and below is vulnerable to Stored XSS via external-link page cvName

Vendor Concrete Cms
Product Concrete CMS
Weakness CWE-79 · XSS
Published May 21, 2026
Last update May 22, 2026
View on NVD All CVEs

CVSS base score

2.0/10
Attack vector Network
Attack complexity Low
Privileges required High
User interaction —
Confidentiality —
Integrity —

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

What the vulnerability does

01Description

Concrete CMS 9.5.0 and below is vulnerable to Stored XSS via external-link page cvName because updateCollectionAliasExternal bypasses being sanitized. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 2.0 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N.  Thanks Yonatan Drori (Tenzai) for reporting.

Key dates

02Disclosure timeline

May 21, 2026 CVE published
May 22, 2026 Record updated