Pre-Authentication Command Injection in DrayTek VigorSwitch Models
CVE-2026-71921

9.3CRITICAL

Key Information:

Vendor

Draytek Corporation

Status
Vigorswitch G2540xs
Vigorswitch P2540xs
Vigorswitch Fx2120
Vigorswitch G2282x
Vendor
CVE Published:
24 August 2026

What is CVE-2026-71921?

DrayTek VigorSwitch models are affected by a pre-authentication command injection vulnerability in the setget.cgi interface. This issue arises from inadequate filtering of input before command execution, allowing remote attackers to send specially crafted requests. Exploiting this vulnerability could enable attackers to execute arbitrary commands with root privileges, potentially compromising the device's integrity and overall network security.

Affected Version(s)

VigorSwitch FX2120 0 < 3.9.10

VigorSwitch G1280 0 < 2.9.10

VigorSwitch G1282 0 < 2.9.10

References

https://www.draytek.com/about/security-advisory/multiple-...
vendor-advisory
https://www.vulncheck.com/advisories/draytek-vigorswitch-...
third-party-advisory

CVSS V4

Score:
9.3
Severity:
CRITICAL
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Jincheng Wang (@winmt)
Le Yu (Nanjing University of Posts and Telecommunications)
Xiapu Luo (The Hong Kong Polytechnic University)
.