CVE-2026-8197CWE-79

Concrete CMS 9.5.0 and below is vulnerable to Stored XSS via OAuth integration name

High · published May 21, 2026

CVSS v4.0
7.3
EPSS
0%
Percentile
15.9
In the wild
Unconfirmed
What it is

Concrete CMS 9.5.0 and below is vulnerable to Stored XSS via OAuth integration name. The OAuth authorize template renders the integration name (admin-controlled) through Concrete's t() translation helper as a sprintf-style format. The <strong>...</strong> wrap is built by PHP string interpolation before t() runs, so the integration name lands in the translated output as raw HTML. A rogue admin could potentially snoop on login submissions.The Concrete CMS security team gave this vulnerability a CVSS v.4.0 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 Yonatan Drori (Tenzai) for reporting.

The record
Technical detail
CVSS v4.0
7.3 · HIGH
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
EPSS
0.00253 · 15.9th percentile
Weakness
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Published
2026-05-21T20:29Z
EPSS history
Timeline
  • 21 MAY 20:29Z
    Concrete CMS 9.5.0 and below is vulnerable to Stored XSS via OAuth integration name
    cvelistv5