CVE-2021-20125

Name: CVE-2021-20125
Creator: NVD / NIST
Published: 2021-10-13T16:15:07.437+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 3.82%

Last modified Jun 17, 2026

CVE-2021-20125 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. An arbitrary file upload and directory traversal vulnerability exists in the file upload functionality of DownloadFileServlet in Draytek VigorConnect 1.6.0-B3. An unauthenticated attacker could leverage this vulnerability to upload files to any location on the target operating system with root privileges.. EPSS estimates a 3.82% chance of exploitation in the next 30 days.

Description

An arbitrary file upload and directory traversal vulnerability exists in the file upload functionality of DownloadFileServlet in Draytek VigorConnect 1.6.0-B3. An unauthenticated attacker could leverage this vulnerability to upload files to any location on the target operating system with root privileges.

Metrics

CVSS 3.1

9.8/10

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

EPSS Probability

3.82%

88.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions	Update
Draytek	Vigorconnect	1.6.0	Beta3

References

https://www.tenable.com/security/research/tra-2021-42Exploit, Third Party Advisory
https://www.tenable.com/security/research/tra-2021-42Exploit, Third Party Advisory

Timeline

Published: Oct 13, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-20125?

How severe is CVE-2021-20125?

CVE-2021-20125 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 3.82% probability of exploitation in the next 30 days.

How do I fix CVE-2021-20125?

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-2021-20125?

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

Scan your code now

Source: NVD / NIST