CVE-2020-20266

Name: CVE-2020-20266
Creator: NVD / NIST
Published: 2021-05-19T12:15:07.813+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 2.10%

Last modified Jun 17, 2026

CVE-2020-20266 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. Mikrotik RouterOs before 6.47 (stable tree) suffers from a memory corruption vulnerability in the /nova/bin/dot1x process. An authenticated remote attacker can cause a Denial of Service (NULL pointer dereference).. EPSS estimates a 2.10% chance of exploitation in the next 30 days.

Description

Mikrotik RouterOs before 6.47 (stable tree) suffers from a memory corruption vulnerability in the /nova/bin/dot1x process. An authenticated remote attacker can cause a Denial of Service (NULL pointer dereference).

Metrics

CVSS 3.1

6.5/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

2.10%

79.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Mikrotik	Routeros	< 6.47

References

https://github.com/cq674350529/pocs_slides/blob/master/pocs/MikroTik/vul_dot1x/README.mdBroken Link, Third Party Advisory
https://seclists.org/fulldisclosure/2021/May/11Exploit, Mailing List, Third Party Advisory
https://github.com/cq674350529/pocs_slides/blob/master/pocs/MikroTik/vul_dot1x/README.mdBroken Link, Third Party Advisory
https://seclists.org/fulldisclosure/2021/May/11Exploit, Mailing List, Third Party Advisory

Timeline

Published: May 19, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-20266?

How severe is CVE-2020-20266?

CVE-2020-20266 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 2.10% probability of exploitation in the next 30 days.

How do I fix CVE-2020-20266?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-20266?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST