Overview
Draytek VigorConnect contains a path traversal vulnerability in the DownloadFileServlet endpoint. An unauthenticated attacker could leverage this vulnerability to download arbitrary files from the underlying operating system with root privileges.
https://www.draytek.com/about/security-advisory/vigorconnect-software-security-vulnerability-(cve-2021-20123-cve-2021-20129); https://nvd.nist.gov/vuln/detail/CVE-2021-20123
Key Details
| Property | Value |
|---|---|
| CVE ID | CVE-2021-20123 |
| Vendor / Product | DrayTek — VigorConnect |
| NVD Published | 2021-10-13 |
| NVD Last Modified | 2025-11-03 |
| CVSS 3.1 Score | 7.5 |
| CVSS 3.1 Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
| Severity | HIGH |
| CWE | CWE-22 |
| CISA KEV Added | 2024-09-03 |
| CISA KEV Deadline | 2024-09-24 |
| Known Ransomware Use | No |
CVSS 3.1 Breakdown
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
Required Action
CISA BOD 22-01 Deadline: 2024-09-24.
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Timeline
| Date | Event |
|---|---|
| 2024-09-03 | Added to CISA Known Exploited Vulnerabilities catalog |
| 2024-09-24 | CISA BOD 22-01 remediation deadline |
References
| Resource | Type |
|---|---|
| NVD — CVE-2021-20123 | Vulnerability Database |
| CISA KEV Catalog Entry | US Government |