RCE in Draytek Vigor 300b
CVE-2026-3040
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 lea…
Vulnerability class: Command Injection (OS Command Injection)
EPSS: 0.004 (63.9th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 4.7 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L.
Affected products
- Draytek Vigor 300b — versions 1.5.1.0, 1.5.1.1, 1.5.1.2
- Draytek Vigor300b
- Draytek Vigor300b_firmware
Weakness classification (CWE)
References
- VDB-347394 | DrayTek Vigor 300B Web Management uploadlangs cgiGetFile os command injection (technical-description, Third Party Advisory, VDB Entry, vdb-entry)
- VDB-347394 | CTI Indicators (IOB, IOC, TTP, IOA) (signature, Permissions Required, permissions-required, Third Party Advisory, VDB Entry)
- Submit #757126 | DrayTek Vigor 300B v1.5.1.6 OS Command Injection (Third Party Advisory, VDB Entry, third-party-advisory)
- cna@vuldb.com (issue-tracking, Exploit, exploit, Issue Tracking)
Frequently asked questions
- What is CVE-2026-3040?
- CVE-2026-3040 is a medium-severity vulnerability in Draytek Vigor 300b, classified under Command Injection. CVSS score: 4.7/10. Published 2026-02-23.
- How severe is CVE-2026-3040?
- Medium severity. CVSS v3 base score is 4.7 out of 10.