THREATPORT/VULNERABILITY/CVE-2026-3040
MEDIUM SEVERITY

CVE-2026-3040

Vigor300b Firmware vulnerability

CVSS
4.7
EPSS
8.8%
EPSS pct
95th
Exploited
No known
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.
Affected vendor
Draytek
Affected product
Vigor300b Firmware
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L
Weakness type (CWE)
Published
2026-02-23

Risk analysis

Based on its CVSS vector, this vulnerability is exploitable over the network, low attack complexity, requiring high privileges, no user interaction. Successful exploitation leads to low impact to confidentiality, low impact to integrity, low impact to availability.

Its EPSS score of 8.8% reflects a lower probability of exploitation activity in the wild over the next 30 days, placing it above 95% of all scored CVEs.

Check your external exposure to CVE-2026-3040

  • Confirm whether Draytek Vigor300b Firmware is running on any internet-facing host or subdomain.
  • Match discovered service fingerprints against the version affected by CVE-2026-3040.
  • Prioritise remediation if the asset is public, business-critical, or near authentication/payment flows.

How ThreatPort helps with CVE-2026-3040

ThreatPort's external attack surface scanner checks your internet-facing assets — agentlessly, from the outside in — for the exposed services and versions that CVE-2026-3040 affects, then prioritises the finding by real risk using CISA KEV and FIRST.org EPSS.

Run a free external exposure scan

Are you exposed to CVE-2026-3040?

Run an instant, non-intrusive external scan to check your attack surface for CVE-2026-3040.

Start free scan

No credit card. Agentless.

Related vulnerabilities

MEDIUM
CVE-2015-6719
Acrobat vulnerability
MEDIUM
CVE-2015-6720
Acrobat vulnerability
MEDIUM
CVE-2015-6721
Acrobat vulnerability