What is CVE-2021-41634?

CVE-2021-41634 is a medium-severity vulnerability in Melag FTP Server, classified under Observable Discrepancy. CVSS score: 5.3/10. Published 2022-06-24.

How severe is CVE-2021-41634?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Vulnerability in Melag FTP Server

CVE-2021-41634

A user enumeration vulnerability in MELAG FTP Server 2.2.0.4 allows an attacker to identify valid FTP usernames.

Published 2022-06-24 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.010 (60.7th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 61st percentile — 60.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.009 · newest: 0.010 · change: +0.000

Affected products

Melag FTP Server — versions 2.2.0.4

Weakness classification (CWE)

CWE-203 — Observable Discrepancy

References

www.securesystems.de/blog/advisory-and-exploitation-the-melag-ftp-server/ (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2021-41634?: CVE-2021-41634 is a medium-severity vulnerability in Melag FTP Server, classified under Observable Discrepancy. CVSS score: 5.3/10. Published 2022-06-24.
How severe is CVE-2021-41634?: Medium severity. CVSS v3 base score is 5.3 out of 10.