What is CVE-2021-22949?

CVE-2021-22949 is a medium-severity vulnerability in Concretecms Concrete Cms, classified under Cross-Site Request Forgery (CSRF). CVSS score: 5.4/10. Published 2021-09-23.

How severe is CVE-2021-22949?

Medium severity. CVSS v3 base score is 5.4 out of 10.

CSRF in Concretecms Concrete Cms

CVE-2021-22949

A CSRF in Concrete CMS version 8.5.5 and below allows an attacker to duplicate files which can lead to UI inconvenience, and exhaustion of disk space.Credit for discovery: "Solar Security CMS Research Team"

Vulnerability class: CSRF (Cross-Site Request Forgery)

Published 2021-09-23 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L.

EPSS exploit prediction

EPSS: 0.004 (27.3th percentile), scored 2026-10-07.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 27th percentile — 27.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Concretecms Concrete Cms
Https://github.com/concrete5/concrete5 — versions Fixed in version 8.5.6

Weakness classification (CWE)

CWE-352 — Cross-Site Request Forgery (CSRF)

References

hackerone.com/reports/1102225 (Permissions Required)
documentation.concretecms.org/developers/introduction/version-history/856-relea… (Release Notes)

Frequently asked questions

What is CVE-2021-22949?: CVE-2021-22949 is a medium-severity vulnerability in Concretecms Concrete Cms, classified under Cross-Site Request Forgery (CSRF). CVSS score: 5.4/10. Published 2021-09-23.
How severe is CVE-2021-22949?: Medium severity. CVSS v3 base score is 5.4 out of 10.