Ch22 FirmwareOperating system · Tenda

CVE-2025-13400

CRITICAL · 9.8 CVSS v3.1 Published 2025-11-19
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
Public exploit 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
A vulnerability was detected in Tenda CH22 1.0.0.1. Affected is the function formWrlExtraGet of the file /goform/WrlExtraGet. Performing a manipulation of the argument chkHz results in buffer overflow. Remote exploitation of the attack is possible. The exploit is now public and may be used.

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 · moderate confidence

Buffer overflow vulnerability in Tenda CH22 router firmware 1.0.0.1. The formWrlExtraGet function in /goform/WrlExtraGet fails to properly validate the length of the chkHz parameter before copying it into a fixed-size buffer, allowing remote attackers to overflow the buffer and potentially achieve remote code execution.

MitigationApply vendor firmware update if available; otherwise restrict access to the router's web management interface to trusted networks only, disable remote administration, and monitor for exploitation attempts given the public exploit availability.

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
Ch22 FirmwareOperating system
Affected:= 1.0.0.1

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 device model
    Access the router web interface or check the device label/metadata to confirm the model is Tenda CH22
    Affected if Device is not a Tenda CH22 router (different models are not affected by this specific CVE)
  2. Check firmware version
    Log into the router admin panel (typically at 192.168.0.1) and navigate to System Settings > Firmware Upgrade, or use the command 'cat /proc/version' via telnet/SSH if available, to determine the installed firmware version
    Affected if Firmware version is exactly 1.0.0.1 (this is the only affected version per vendor disclosure)
  3. Verify vulnerable web endpoint exists
    Send an HTTP GET or POST request to http://[router-ip]/goform/WrlExtraGet using a tool like curl or a browser developer console. A 200 OK response or any server response (rather than a 404) indicates the endpoint is present
    Affected if The /goform/WrlExtraGet endpoint returns a response (indicating the function is compiled into the firmware)
  4. Test chkHz parameter handling
    Send a POST request to /goform/WrlExtraGet with a crafted chkHz parameter containing an unusually long string (e.g., 200+ characters). Observe if the router hangs, crashes, or returns an error, or use a tool like Burp Suite to test for buffer overflow behavior
    Affected if The router accepts unusually long chkHz input without rejecting it, or exhibits abnormal behavior (crash/restart) indicating the buffer is not properly validated

You are affected if you have a Tenda CH22 router running firmware version 1.0.0.1 with the /goform/WrlExtraGet endpoint accessible and the chkHz parameter accepting oversized input without validation.

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 vendor firmware update if available; otherwise restrict access to the router's web management interface to trusted networks only, disable remote administration, and monitor for exploitation attempts given the public exploit availability.

Fix this in Ch22 Firmware Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing4.0 h
  • Review / QA2.0 h
18.0 hours of engineering $3,200
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Scan for this in your stack

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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-2025-13400 in production — separate from our analysis above.

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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
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