What is CVE-2021-28909?

CVE-2021-28909 is a critical-severity vulnerability in Bab-Technologie Eibport, classified under Improper Restriction of Excessive Authentication Attempts. CVSS score: 9.8/10. Published 2021-09-09.

How severe is CVE-2021-28909?

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

Vulnerability in Bab-Technologie Eibport

CVE-2021-28909

BAB TECHNOLOGIE GmbH eibPort V3 prior version 3.9.1 allow unauthenticated attackers to access uncontrolled the login service at /webif/SecurityModule in a brute force attack. The password could be weak and default username is known as 'admin'. This is usable and part of an attack chain to gain SSH root access.

Published 2021-09-09 · 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: 0.014 (71.2th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 71st percentile — 71.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.014 · newest: 0.014 · change: 0.000

Affected products

Bab-Technologie Eibport — versions v3
Bab-Technologie Eibport Firmware

Weakness classification (CWE)

CWE-307 — Improper Restriction of Excessive Authentication Attempts

References

psytester.github.io/CVE-2021-28909 (Third Party Advisory)

Frequently asked questions

What is CVE-2021-28909?: CVE-2021-28909 is a critical-severity vulnerability in Bab-Technologie Eibport, classified under Improper Restriction of Excessive Authentication Attempts. CVSS score: 9.8/10. Published 2021-09-09.
How severe is CVE-2021-28909?: Critical severity. CVSS v3 base score is 9.8 out of 10.