TI-2021-03423 Aliases CVE-2021-20123 GHSA-gc9m-33cp-rmpj

Path traversal in Draytek VigorConnect

CRITICAL 90Exploited in the wildCWE-22Published 2021-10-13 · Updated 2025-10-21

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Information disclosure
Confidentiality · integrity · availability: High · None · None
Fix status: No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-22 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation Active In CISA KEV since 2024-09-03CISA due date 2024-09-24

EPSS 0.89654 99th percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by NVD

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Active
Automatable: Yes
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
—	Draytek VigorConnect	1.6.0-B3	—	No fix listed	CNA

Draytek VigorConnect Vendor— Affected 1.6.0-B3 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:draytek:vigorconnect:1.6.0:beta3::::::	1.6.0 beta3	Vulnerable	DrayTek

cpe:2.3:a:draytek:vigorconnect:1.6.0:beta3:*:*:*:*:*:* Versions 1.6.0 beta3 Vulnerable ·DrayTek

Remediation

No fixed version listed by the sources yet.

Timeline

2024-09-03 Added to CISA KEV
2026-10-02 Threatist record created from CVE-2021-20123
2026-10-03 Alias added: GHSA-gc9m-33cp-rmpj

References

Exploit 1

https://www.tenable.com/security/research/tra-2021-42

TI-2021-03424 Path traversal in Draytek VigorConnect KEVCVSS 3.1HIGH 7.5
TI-2021-03425 Path traversal in Draytek VigorConnect CVSS 3.1CRITICAL 9.8
TI-2021-03426 Cross-site request forgery in Draytek VigorConnect CVSS 3.1HIGH 8.8
TI-2021-03427 An arbitrary file deletion vulnerability exists in the file delete functionality of the… CVSS 3.1HIGH 8.1
TI-2021-03429 Sensitive information in log files in Draytek VigorConnect CVSS 3.1HIGH 7.5
TI-2021-03428 Cross-site scripting in Draytek VigorConnect CVSS 3.1MEDIUM 5.4

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences