What is CVE-2021-40097?

CVE-2021-40097 is a high-severity vulnerability in Concretecms Concrete Cms, classified under Path Traversal. CVSS score: 8.8/10. Published 2021-09-27.

How severe is CVE-2021-40097?

High severity. CVSS v3 base score is 8.8 out of 10.

Path Traversal in Concretecms Concrete Cms

CVE-2021-40097

An issue was discovered in Concrete CMS through 8.5.5. Authenticated path traversal leads to to remote code execution via uploaded PHP code, related to the bFilename parameter.

Vulnerability class: Path Traversal (Directory Traversal)

Published 2021-09-27 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.025 (84.3th percentile), scored 2026-10-09.

Low probability of exploitation in the next 30 days, but still tracked. 84th percentile — 84.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.025 · newest: 0.025 · change: 0.000

Affected products

Concretecms Concrete Cms

Weakness classification (CWE)

CWE-22 — Path Traversal

References

hackerone.com/reports/1102067 (Permissions Required, Third Party Advisory)
documentation.concretecms.org/developers/introduction/version-history/856-relea… (Release Notes, Vendor Advisory)

Frequently asked questions

What is CVE-2021-40097?: CVE-2021-40097 is a high-severity vulnerability in Concretecms Concrete Cms, classified under Path Traversal. CVSS score: 8.8/10. Published 2021-09-27.
How severe is CVE-2021-40097?: High severity. CVSS v3 base score is 8.8 out of 10.