CVE-2022-0342
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 · uneditedAn authentication bypass vulnerability in the CGI program of Zyxel USG/ZyWALL series firmware versions 4.20 through 4.70, USG FLEX series firmware versions 4.50 through 5.20, ATP series firmware versions 4.32 through 5.20, VPN series firmware versions 4.30 through 5.20, and NSG series firmware versions V1.20 through V1.33 Patch 4, which could allow an attacker to bypass the web authentication and obtain administrative access of the device.
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 confidenceThis is an authentication bypass vulnerability in the CGI program of multiple Zyxel security appliance product lines (USG/ZyWALL, USG FLEX, ATP, VPN, NSG). The flaw allows unauthenticated attackers to bypass web authentication mechanisms and gain administrative privileges on affected devices.
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>= 4.20, < 4.71>= 4.20, < 4.71>= 4.20, < 4.71>= 4.20, < 4.71>= 4.20, < 4.71>= 4.20, < 4.71>= 4.20, < 4.71>= 4.50, <= 5.20CVSS 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 checksWork through these to decide whether this CVE applies to you.
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Identify device model and firmware versionLog into the Zyxel device web interface and navigate to System > Status or the About page to view the exact model name and firmware version. Alternatively, access the CLI and run the command 'show system-info' or 'sysinfo' to retrieve firmware details.Affected if The device model matches one of the affected models (USG40, USG40w, USG60, USG60w, Zywall 110, Zywall 310, Zywall 1100, USG Flex 100) AND the firmware version falls within the affected ranges (>= 4.20 and < 4.71 for USG/Zywall models, or >= 4.50 and <= 5.20 for USG Flex 100).
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Confirm web authentication is enabledIn the web interface, navigate to Configuration > Security Policy > Authentication Settings or similar, and verify if web-based authentication is enabled for admin access.Affected if Web authentication is enabled, as this is the attack vector that the vulnerability exploits.
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Check for unauthorized admin accountsIn the web interface, navigate to Administration > User Account or Configuration > Object > User to review all configured administrator accounts. Look for any unexpected or unknown accounts that may indicate prior exploitation.Affected if New or unrecognized administrator accounts exist that were not created by your organization.
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Review access logs for suspicious CGI accessIn the web interface, go to Log > View Logs or System > Log. Search for entries involving the CGI program (often /cgi-bin/) that show successful authentication or administrative actions from IP addresses you do not recognize.Affected if Logs contain unauthorized administrative actions or authentication bypass attempts, particularly involving CGI endpoints.
The device is affected if it is a vulnerable USG/ZyWALL/USG Flex model running firmware within the specified version ranges and web authentication is enabled.
Generated from the published advisory. Verify against your own configuration.
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 · scoped4.71
Apply vendor-supplied firmware updates to all affected Zyxel devices; immediately review access logs for unauthorized administrative access and consider network segmentation to limit exposure until patches can be applied.
Firmware version 4.71 or later for USG/ZyWALL series; Firmware version 5.21 or later for USG Flex 100
- 1. Identify the specific device model from the affected product list (Usg40, Usg40w, Usg60, Usg60w, Zywall 110, Zywall 310, Zywall 1100, or Usg Flex 100)
- 2. Access the device's web management interface or CLI
- 3. Navigate to the firmware upgrade section (typically under Maintenance > Firmware Upgrade or System > Firmware)
- 4. Download the appropriate firmware version 4.71 or later from Zyxel's official support website (www.zyxel.com)
- 5. Upload the firmware file to the device and initiate the upgrade
- 6. Wait for the upgrade to complete and the device to reboot
- 7. Verify the new firmware version is installed and the device is functioning normally
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation4.0 h
- Implementation6.0 h
- Testing4.0 h
- Review / QA2.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2022-0342 — 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 sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2022-0342 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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