What is CVE-2021-41403?

CVE-2021-41403 is a critical-severity vulnerability in Flatcore Flatcore-Cms, classified under Server-Side Request Forgery (SSRF). CVSS score: 9.8/10. Published 2022-06-15.

How severe is CVE-2021-41403?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2021-41403 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

SSRF in Flatcore Flatcore-Cms

CVE-2021-41403

flatCore-CMS version 2.0.8 calls dangerous functions, causing server-side request forgery vulnerabilities.

Vulnerability class: SSRF (Server-Side Request Forgery)

Published 2022-06-15 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.191 (97.2th percentile), scored 2026-09-28.

Moderate probability of exploitation in the next 30 days — watch for active exploitation reports. 97th percentile — 97.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.186 · newest: 0.191 · change: +0.005

Affected products

Flatcore Flatcore-Cms — versions 2.0.8

Weakness classification (CWE)

CWE-918 — Server-Side Request Forgery (SSRF)

Public proof-of-concept exploits

ARPSyndicate/cve-scores

References

github.com/flatCore/flatCore-CMS/issues/60 (Exploit, Patch, Third Party Advisory)

Frequently asked questions

What is CVE-2021-41403?: CVE-2021-41403 is a critical-severity vulnerability in Flatcore Flatcore-Cms, classified under Server-Side Request Forgery (SSRF). CVSS score: 9.8/10. Published 2022-06-15.
How severe is CVE-2021-41403?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2021-41403 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.