dbcve.org
Nas326 FirmwareOperating system · Zyxel

CVE-2024-6342

CRITICAL · 9.8 CVSS v3.1 Published 2024-09-10
Fix available
A fix is available. Upgrade to 5.21 or later.
See remediation →
100/100
Remediation priority · Urgent
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
**UNSUPPORTED WHEN ASSIGNED** A command injection vulnerability in the export-cgi program of Zyxel NAS326 firmware versions through V5.21(AAZF.18)C0 and NAS542 firmware versions through V5.21(ABAG.15)C0 could allow an unauthenticated attacker to execute some operating system (OS) commands by sending a crafted HTTP POST request.

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 command injection vulnerability exists in the export-cgi program of Zyxel NAS326 and NAS542 network-attached storage devices. Unauthenticated attackers can execute arbitrary operating system commands by sending specially crafted HTTP POST requests to the vulnerable CGI endpoint.

MitigationApply vendor firmware updates when released by Zyxel; in the interim, restrict network access to the NAS management interface to prevent unauthenticated attackers from reaching the vulnerable endpoint.

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
Nas326 FirmwareOperating system
Affected:< 5.21\(aazf.18\)c0= 5.21\(aazf.18\)c0
Nas542 FirmwareOperating system
Affected:< 5.21\(abag.15\)c0= 5.21\(abag.15\)c0

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
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/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 Zyxel NAS device model
    Access the NAS web interface admin panel or check the device label/menu to confirm whether the device is a NAS326 or NAS542 model.
    Affected if The device is a Zyxel NAS326 or NAS542 model.
  2. Determine the installed firmware version on NAS326
    Log into the NAS326 web interface, navigate to Administration > Firmware/Recovery, and note the displayed firmware version number.
    Affected if The firmware version is 5.21(aazf.18)c0 or any version lower than 5.21(aazf.18)c0.
  3. Determine the installed firmware version on NAS542
    Log into the NAS542 web interface, navigate to Administration > Firmware/Recovery, and note the displayed firmware version number.
    Affected if The firmware version is 5.21(abag.15)c0 or any version lower than 5.21(abag.15)c0.
  4. Verify export-cgi endpoint accessibility
    Attempt to access the export-cgi program via HTTP POST request to the endpoint (typically /export-cgi or similar path on the device). Check if the endpoint responds to unauthenticated requests.
    Affected if The export-cgi endpoint is reachable from the network without authentication.
  5. Check network exposure of the NAS device
    Review firewall rules, port forwards, or VPN configurations to determine if the NAS management interface and export-cgi are exposed to the internet or untrusted networks.
    Affected if The device is directly accessible from the internet or untrusted networks on ports used for the web interface.

A user is affected if they own a NAS326 or NAS542 device running firmware version equal to or below the specified version thresholds and the export-cgi endpoint is network-accessible.

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.

dbcve · scoped
Upgrade available Upgrade to 5.21 or later
Fixed in 5.21
Interim mitigation

Apply vendor firmware updates when released by Zyxel; in the interim, restrict network access to the NAS management interface to prevent unauthenticated attackers from reaching the vulnerable endpoint.

Recommended fix Moderate confidence

Latest firmware version available from Zyxel for Nas326 (after V5.21(AAZF.18)C0) or Nas542 (after V5.21(ABAG.15)C0)

  1. 1. Identify the exact model number (Nas326 or Nas542) of the affected Zyxel NAS device
  2. 2. Navigate to Zyxel support website (www.zyxel.com) and locate the firmware download section for the specific NAS model
  3. 3. Check for available firmware versions newer than V5.21(AAZF.18)C0 for Nas326 or V5.21(ABAG.15)C0 for Nas542
  4. 4. Download the latest available firmware version from Zyxel's official support page
  5. 5. Follow Zyxel's firmware upgrade instructions specific to the NAS model (typically via web GUI or manual firmware upload)
  6. 6. After upgrade, verify the device is functioning properly
  7. 7. If no newer firmware is available from Zyxel, consider network segmentation or restricting access to the export-cgi endpoint via firewall rules
Caveat Review Zyxel release notes for any configuration or feature changes between versions; backup configuration before upgrading

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Nas326 Firmware Scoped from the published advisory
  • Consultation3.0 h
  • Implementation4.0 h
  • Testing4.0 h
  • Review / QA2.0 h
13.0 hours of engineering $2,280
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,648.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2024-6342 — 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-2024-6342 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