dbcve.org
Actively exploited in the wild. This CVE is on the CISA Known Exploited Vulnerabilities list — treat remediation as urgent. Federal remediation due by 9 Oct 2023. Known ransomware use
Emg2926 FirmwareOperating system · Zyxel

CVE-2017-6884

HIGH · 8.8 CVSS v3.1 Published 2017-04-06
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
In the wild Ransomware Public exploit Remotely reachable 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
A command injection vulnerability was discovered on the Zyxel EMG2926 home router with firmware V1.00(AAQT.4)b8. The vulnerability is located in the diagnostic tools, specifically the nslookup function. A malicious user may exploit numerous vectors to execute arbitrary commands on the router, such as the ping_ip parameter to the expert/maintenance/diagnostic/nslookup URI.

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

Command injection vulnerability in Zyxel EMG2926 router firmware V1.00(AAQT.4)b8. The nslookup diagnostic function at /expert/maintenance/diagnostic/nslookup does not sanitize the ping_ip parameter, allowing injection of arbitrary OS commands via the web interface.

MitigationApply available firmware update from ZyXEL; if no update exists, restrict access to the router's management interface to trusted networks only or replace the end-of-life device.

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
Emg2926 FirmwareOperating system
Affected:= v1.00\(aaqt.4\)b8

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
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:L/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 router model
    Access the router's web admin interface and check the device info page, or check the device label/marking for the model number
    Affected if The device is a Zyxel EMG2926 router
  2. Check the installed firmware version
    Log into the router's web interface and navigate to Status or Maintenance > Firmware section to view the current firmware version
    Affected if The firmware version is v1.00(aaqt.4)b8
  3. Verify the diagnostic nslookup function exists
    Access the URL /expert/maintenance/diagnostic/nslookup on the router's web interface (may require authentication)
    Affected if The nslookup diagnostic page is accessible and accepts input via the ping_ip parameter
  4. Check if remote management is enabled
    Log into the router admin panel and look under Security or Remote Management settings to see if remote access to the admin interface is enabled
    Affected if Remote management is enabled, allowing exploitation from outside the local network

You are affected if you have a Zyxel EMG2926 router running firmware v1.00(aaqt.4)b8 with the diagnostic nslookup function accessible, especially if remote management is enabled.

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 available firmware update from ZyXEL; if no update exists, restrict access to the router's management interface to trusted networks only or replace the end-of-life device.

Fix this in Emg2926 Firmware Exploited in the wild — priority engagement
  • Consultation3.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA1.0 h
10.0 hours of engineering $1,800
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,880.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2017-6884 — 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-2017-6884 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