dbcve.org
D8500 FirmwareOperating system · Netgear

CVE-2018-21093

HIGH · 8.8 CVSS v3.1 Published 2020-04-27
Fix available
A fix is available. Upgrade to 1.0.0.22 / 1.0.0.30 or later.
See remediation →
93/100
Remediation priority · Urgent
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
Certain NETGEAR devices are affected by a stack-based buffer overflow by an unauthenticated attacker. This affects D8500 before 1.0.3.42, EX3700 before 1.0.0.70, EX3800 before 1.0.0.70, EX6000 before 1.0.0.30, EX6100 before 1.0.2.24, EX6120 before 1.0.0.40, EX6130 before 1.0.0.22, EX6150 before 1.0.0.42, EX6200 before 1.0.3.88, EX7000 before 1.0.0.66, R6250 before 1.0.4.26, R6300-2CXNAS before 1.0.3.60, R6300v2 before 1.0.4.28, R6400 before 1.0.1.36, R6400v2 before 1.0.2.52, R6700 before 1.0.1.46, R6900 before 1.0.1.46, R7000 before 1.0.9.28, R7000P before 1.3.1.44, R6900P before 1.3.1.44, R7100LG before 1.0.0.46, R7300 before 1.0.0.68, R7900 before 1.0.2.10, R8000 before 1.0.4.18, R8000P before 1.3.0.10, R7900P before 1.3.0.10, R8500 before 1.0.2.122, R8300 before 1.0.2.122, RBW30 before 2.1.2.6, WN2500RPv2 before 1.0.0.54, and WNR3500Lv2 before 1.2.0.56.

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

A stack-based buffer overflow vulnerability exists in multiple NETGEAR router and wireless extender models. The flaw allows an unauthenticated attacker to overflow a stack-allocated buffer, potentially leading to arbitrary code execution or device compromise. The vulnerability is exploitable without authentication and affects network-adjacent attack surface.

MitigationUpdate affected NETGEAR devices to the specified firmware versions listed in the advisory. If updates are unavailable, consider network segmentation or device replacement to reduce exposure.

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
D8500 FirmwareOperating system
Affected:< 1.0.3.42
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:< 1.0.2.24
Ex6120 FirmwareOperating system
Affected:< 1.0.0.40
Ex6130 FirmwareOperating system
Affected:< 1.0.0.22
Ex6150 FirmwareOperating system
Affected:< 1.0.0.42

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

CVSS:3.1/AV:A/AC:L/PR:N/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 the NETGEAR device model
    Locate the model number on the device label or check the web admin interface (typically at 192.168.1.1) for the device model name under Administration or Router Status
    Affected if The device model is one of: D8500, Ex3700, Ex3800, Ex6000, Ex6100, Ex6120, Ex6130, or Ex6150
  2. Locate the firmware version
    Access the router or extender web admin interface and navigate to Router Status, Administration, or Firmware Update section to view the currently installed firmware version
    Affected if Unable to determine firmware version from the device interface
  3. Compare firmware version against the fixed version for your model
    Match your device model to its fixed version threshold: D8500 requires 1.0.3.42, Ex3700/Ex3800 require 1.0.0.70, Ex6000 requires 1.0.0.30, Ex6100 requires 1.0.2.24, Ex6120 requires 1.0.0.40, Ex6130 requires 1.0.0.22, Ex6150 requires 1.0.0.42. If your version is below this threshold, the device is affected
    Affected if The installed firmware version is a version number lower than the fixed version for your specific model (e.g., Ex3700 on version 1.0.0.50 is affected, but 1.0.0.70 is not)
  4. Confirm network accessibility
    Verify that the device is powered on and accessible on the network (can be pinged or its web interface is reachable)
    Affected if The device is reachable on the network and the vulnerable firmware version is installed

If the device is a NETGEAR D8500, Ex3700, Ex3800, Ex6000, Ex6100, Ex6120, Ex6130, or Ex6150 running firmware below the fixed version for that model and is network-accessible, the environment is affected by this CVE.

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 1.0.0.22 / 1.0.0.30 / 1.0.0.40 or later
Fixed in 1.0.0.221.0.0.301.0.0.40
Interim mitigation

Update affected NETGEAR devices to the specified firmware versions listed in the advisory. If updates are unavailable, consider network segmentation or device replacement to reduce exposure.

Fix this in D8500 Firmware Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,860
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $6,176.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2018-21093 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2018-21093 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