CVE-2021-20123

Draytek VigorConnect Path Traversal Vulnerability

  • High 7.5
  • Exploited: added to CISA KEV 3 Sep 2024

Description

A local file inclusion vulnerability exists in Draytek VigorConnect 1.6.0-B3 in the file download functionality of the DownloadFileServlet endpoint. An unauthenticated attacker could leverage this vulnerability to download arbitrary files from the underlying operating system with root privileges.

Key facts

Published
13 Oct 2021
Last changed
21 Oct 2025
Assigned by
tenable
KEV added
3 Sep 2024
KEV fix due
24 Sep 2024
EPSS
90.332% likely to be exploited in the next 30 days, higher than 99.802% of CVEs (scores for 15 Nov 2026)
SSVC (CISA)
Exploitation: active; Automatable: yes; Technical impact: partial

Severity scores

Each score is shown as its source gave it. They are not averaged or merged.

  • 7.5CVSS 3.1, Highfrom CISA (ADP container)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

What to do

  • Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.CISA KEV required action

Historical context and remediation

This reference retains the original CVE publication date. A recent record update does not mean a new attack occurred.

No separately sourced impact summary is available on this page yet. Consult the description, version data and dated exploitation evidence.

Version statuses below come from the CNA. An “unaffected” version is not necessarily a currently supported release or proof of a patch date. EPSS is a dated risk estimate, not a count of historical attacks.

Read the original CVE record.

Affected products

VendorProductVersions
n/aDraytek VigorConnect
  • 1.6.0-B3 (affected)

Timeline

  1. 13 Oct 2021 Published
  2. 3 Sep 2024 CVE-2021-20123 added to CISA KEV
  3. 3 Sep 2024 Added to the CISA KEV catalogue

Weakness

Practice this bug class

HackZoneLabs has a hands-on lab on Path traversal (CWE-22).

References