Vigor3910 FirmwareOperating system · Draytek

CVE-2024-46596

HIGH · 7.5 CVSS v3.1 Published 2024-09-18
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Draytek Vigor 3910 v4.3.2.6 was discovered to contain a buffer overflow in the sAct parameter at v2x00.cgi. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted input.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

A buffer overflow vulnerability exists in the sAct parameter of the v2x00.cgi web interface on Draytek Vigor 3910 devices running firmware v4.3.2.6. Attackers can send specially crafted input that overflows a buffer, causing the device to crash and resulting in a Denial of Service condition.

MitigationApply any available firmware update from Draytek. If no patch exists, restrict network access to the device's web management interface to trusted sources only, as exploitation requires sending HTTP requests to v2x00.cgi.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Vigor3910 FirmwareOperating system
Affected:= 4.3.2.6

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify the device model
    Log into the device's web管理界面 or check the device label to confirm the model is Draytek Vigor 3910
    Affected if The device is not a Draytek Vigor 3910, then this CVE does not apply
  2. Check the installed firmware version
    Navigate to the web interface System Maintenance > Firmware Upgrade or System Status page to view the current firmware version
    Affected if The firmware version is exactly 4.3.2.6 - this is the affected version
  3. Verify if the v2x00.cgi endpoint is accessible
    Attempt to access https://<device_ip>/v2x00.cgi from an authorized network location to confirm the web interface is reachable
    Affected if The v2x00.cgi endpoint is accessible from untrusted networks - exploitation requires sending HTTP requests to this CGI script
  4. Check for signs of device crash or unresponsiveness
    Attempt to access the web interface or ping the device to verify it is responsive. Review any system logs available via the web interface for crash indicators
    Affected if The device is unresponsive, crashing repeatedly, or showing signs of a denial of service condition since the vulnerability causes crashes

You are affected if you have a Draytek Vigor 3910 device running firmware version 4.3.2.6 with the web interface accessible, especially if the device exhibits crashes or unresponsiveness.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply any available firmware update from Draytek. If no patch exists, restrict network access to the device's web management interface to trusted sources only, as exploitation requires sending HTTP requests to v2x00.cgi.

Fix this in Vigor3910 Firmware Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA1.0 h
10.0 hours of engineering $1,750
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,800.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2024-46596 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2024-46596 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data