What is CVE-2019-3981?

CVE-2019-3981 is a low-severity vulnerability in Mikrotik Routeros, classified under Channel Accessible by Non-Endpoint. CVSS score: 3.7/10. Published 2020-01-14.

How severe is CVE-2019-3981?

Low severity. CVSS v3 base score is 3.7 out of 10.

Vulnerability in Mikrotik Routeros

CVE-2019-3981

MikroTik Winbox 3.20 and below is vulnerable to man in the middle attacks. A man in the middle can downgrade the client's authentication protocol and recover the user's username and MD5 hashed password.

Published 2020-01-14 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 3.7 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.011 (65.3th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 65th percentile — 65.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.011 · newest: 0.011 · change: 0.000

Affected products

Mikrotik Routeros
Mikrotik Winbox — versions Winbox 3.20 and below.

Weakness classification (CWE)

CWE-300 — Channel Accessible by Non-Endpoint

References

www.tenable.com/security/research/tra-2020-01 (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2019-3981?: CVE-2019-3981 is a low-severity vulnerability in Mikrotik Routeros, classified under Channel Accessible by Non-Endpoint. CVSS score: 3.7/10. Published 2020-01-14.
How severe is CVE-2019-3981?: Low severity. CVSS v3 base score is 3.7 out of 10.