CVE-2026-8353
Low
No strong exploitation signal.
CVSS base
4.8
MEDIUM
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
EPSS — probability of exploitation (30 days)
0.1%
4.5th percentile
CISA KEV
Not listed
Weakness / dates
CWE-79
Published 2026-05-22 · modified 2026-07-23
CVSS breakdown
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
| Attack Vector | N | Network |
| Attack Complexity | L | Low |
| Privileges Required | H | High |
| User Interaction | R | Required |
| Scope | C | Changed |
| Confidentiality | L | Low |
| Integrity | L | Low |
| Availability | N | None |
Timeline
- 2026-05-22 — Published (NVD)
- 2026-07-23 — Last modified (NVD)
Description
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.