CVE-2026-3040 MEDIUM

CVE-2026-3040: DrayTek Vigor 300B Web Management uploadlangs cgiGetFile os command injection

Vendor Draytek
Product Vigor 300B
Weakness CWE-78
Published February 23, 2026
Last update February 25, 2026

CVSS base score

5.1/10
Attack vector Network
Attack complexity Low
Privileges required High
User interaction None
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P

What the vulnerability does

01Description

A vulnerability was identified in DrayTek Vigor 300B up to 1.5.1.6. This affects the function cgiGetFile of the file /cgi-bin/mainfunction.cgi/uploadlangs of the component Web Management Interface. The manipulation of the argument File leads to os command injection. The attack may be initiated remotely. The exploit is publicly available and might be used. The vendor confirms that "300B is EoL, and this is an authenticated vulnerability. We don't plan to fix it." This vulnerability only affects products that are no longer supported by the maintainer.

Key dates

02Disclosure timeline

February 23, 2026 CVE published
February 25, 2026 Record updated