CVE-2026-71931

Multiple DrayTek VigorSwitch models contain a command injection vulnerability in the tftp_upgrade function. The vulnerability is caused by insufficient filtering before the filename field is concatenated into a command. A remote attacker can trigger this vulnerability via crafted input to execute arbitrary commands with root privileges. Exploitation requires valid administrative credentials for the device's web management interface.

CVSS v3 7.2 HIGH

7.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.draytek.com/about/security-advisory/multiple-vulnerabilities-in-vigorswitch-series-august-2026/
https://www.vulncheck.com/advisories/draytek-vigorswitch-multiple-models-os-command-injection-via-tftp-upgrade

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-24 18:17

Updated : 2026-08-27 17:19

NVD link : CVE-2026-71931

Mitre link : CVE-2026-71931

CVE.ORG link : CVE-2026-71931

JSON object : View

Products Affected

No product.

CWE

CWE-78

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

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The vulnerability is caused by insufficient filtering before the filename field is concatenated into a command. A remote attacker can trigger this vulnerability via crafted input to execute arbitrary commands with root privileges. Exploitation requires valid administrative credentials for the device's web management interface."}], "lastModified": "2026-08-27T17:19:48.677", "sourceIdentifier": "disclosure@vulncheck.com"}