Is CVE-2026-3040 actively exploited?

CVE-2026-3040 has no public evidence of in-the-wild exploitation as of 2026-02-26.

What is the CVSS score for CVE-2026-3040?

CVE-2026-3040 has a CVSS score of 5.1 (MEDIUM severity). 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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X.

How do I patch CVE-2026-3040?

Patch guidance is available from draytek security advisories. CVEDatabase generates AI-assisted remediation guidance on demand for CVE-2026-3040.

Which products are affected by CVE-2026-3040?

1 product: draytek vigor300b firmware.

CVE-2026-3040 - remediation guidance & executive summary

Description

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.

CVSS Metrics

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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector: network
Complexity: low
Privileges: high
User Action: none
Confidentiality: undefined
Integrity: undefined
Availability: undefined
Weaknesses: CWE-77 · Command Injection CWE-78 · OS Command Injection CWE-78 · OS Command Injection

Metadata

Primary Vendor: DRAYTEK
Published: 2/23/2026
Last Modified: 2/26/2026
Source: NIST NVD
Note: Verify all details with official vendor sources before applying patches.

CVE-2026-3040

Description

CVSS Metrics

Metadata

Affected Products

Remediation Guidance

Executive Summary