D6220 FirmwareOperating system · Netgear

CVE-2019-20731

MEDIUM · 6.7 CVSS v3.1 Published 2020-04-16
Fix available
A fix is available. Upgrade to 1.0.0.30 / 1.0.0.40 or later.
See remediation →
69/100
Remediation priority · Elevated
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
Certain NETGEAR devices are affected by a buffer overflow by an authenticated user. This affects D6220 before 1.0.0.40, D6400 before 1.0.0.74, D7000v2 before 1.0.0.74, D8500 before 1.0.3.39, EX3700 before 1.0.0.70, EX3800 before 1.0.0.70, EX6000 before 1.0.0.30, EX6100 before 1.0.2.22, EX6120 before 1.0.0.40, EX6130 before 1.0.0.22, EX6150v1 before 1.0.0.42, EX6200 before 1.0.3.88, EX7000 before 1.0.0.66, R6250 before 1.0.4.20, R6300v2 before 1.0.4.18, R6400v2 before 1.0.2.52, R6700 before 1.0.1.44, R6900 before 1.0.1.46, R7000 before 1.0.9.26, R6900P before 1.3.0.20, R7000P before 1.3.0.20, R7100LG before 1.0.0.34, R7300DST before 1.0.0.62, R8000 before 1.0.4.12, R7900P before 1.3.0.10, R8000P before 1.3.0.10, R8300 before 1.0.2.116, R8500 before 1.0.2.116, WN2500RPv2 before 1.0.1.54, and WNDR3400v3 before 1.0.1.18.

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 · high confidence

Buffer overflow vulnerability in NETGEAR router firmware (multiple models) that can be exploited by an authenticated user, likely allowing arbitrary code execution or denial of service. The vulnerability exists in the web management interface and requires valid credentials for exploitation.

MitigationUpdate affected devices to the specified firmware versions. Since the vulnerability requires authentication, ensure strong credentials and consider network segmentation to limit exposure to untrusted users.

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
D6220 FirmwareOperating system
Affected:< 1.0.0.40
D6400 FirmwareOperating system
Affected:< 1.0.0.74
D7000 FirmwareOperating system
Affected:< 1.0.0.74
D8500 FirmwareOperating system
Affected:< 1.0.3.39
Ex3700 FirmwareOperating system
Affected:< 1.0.0.70
Ex3800 FirmwareOperating system
Affected:< 1.0.0.70
Ex6000 FirmwareOperating system
Affected:< 1.0.0.30
Ex6100 FirmwareOperating system
Affected:< 1.0.2.22

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
Local
Complexity
Low
Privileges
High
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/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 router model
    Locate the model number on the device label or log into the web management interface (typically at 192.168.1.1) and check the status or administration page for the exact model designation
    Affected if The model is one of: D6220, D6400, D7000, D8500, Ex3700, Ex3800, Ex6000, or Ex6100
  2. Check installed firmware version
    In the router web admin interface, navigate to the Administration or Firmware Upgrade section to view the current firmware version. Alternatively, check the router status page which typically displays the firmware version under system information
    Affected if The displayed firmware version is below the threshold for your specific model (D6220: 1.0.0.40, D6400/D7000: 1.0.0.74, D8500: 1.0.3.39, Ex3700/Ex3800: 1.0.0.70, Ex6000: 1.0.0.30, Ex6100: 1.0.2.22)
  3. Verify web management interface is accessible
    Attempt to reach the router web interface from the network segment in question by navigating to the router IP address in a browser. Check if the login page loads
    Affected if The web management interface is reachable from network segments where untrusted users could potentially obtain valid credentials
  4. Confirm authentication method in use
    Review the router security settings to determine if default credentials are in use or if strong, unique credentials have been configured for web management access
    Affected if Default credentials remain unchanged or weak credentials are used, increasing the likelihood of successful exploitation

You are affected if your router model matches one of the eight listed models AND your installed firmware version is below the specified threshold AND the web management interface is accessible to potential attackers.

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
Upgrade available Upgrade to 1.0.0.30 / 1.0.0.40 / 1.0.0.70 or later
Fixed in 1.0.0.301.0.0.401.0.0.70
Interim mitigation

Update affected devices to the specified firmware versions. Since the vulnerability requires authentication, ensure strong credentials and consider network segmentation to limit exposure to untrusted users.

Fix this in D6220 Firmware Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA2.0 h
20.0 hours of engineering $3,500
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2019-20731 — 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-2019-20731 in production — separate from our analysis above.

No notes yet

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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