Ax1806 FirmwareOperating system · Tenda

CVE-2024-4239

HIGH · 8.8 CVSS v3.1 Published 2024-04-26
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
94/100
Remediation priority · Urgent
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 vulnerability was found in Tenda AX1806 1.0.0.1 and classified as critical. Affected by this issue is the function formSetRebootTimer of the file /goform/SetRebootTimer. The manipulation of the argument rebootTime leads to stack-based buffer overflow. The attack may be launched remotely. The exploit has been disclosed to the public and may be used. VDB-262130 is the identifier assigned to this vulnerability. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.

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 the formSetRebootTimer function of Tenda AX1806 routers (firmware 1.0.0.1). The function processes the rebootTime argument without proper bounds checking, allowing an attacker to overflow a stack-based buffer by providing an overly long value, potentially achieving remote code execution.

MitigationSince the vendor has not responded to the disclosure and no patch is available, implement network-level controls such as restricting access to the router's web management interface to trusted internal IPs only, or consider replacing the device with a model that receives security updates.

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
Ax1806 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
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
    Locate the device label or check the web management interface for the exact model number (Tenda AX1806).
    Affected if The device is NOT a Tenda AX1806 router.
  2. Check the firmware version
    Access the router's web management interface (typically at 192.168.0.1) and navigate to System Settings > Firmware Upgrade, or use the telnet/SSH interface and run 'cat /etc/version' or 'ver' to retrieve the firmware version.
    Affected if The firmware version is 1.0.0.1.
  3. Verify the web management interface is active
    Attempt to access the router's HTTP/HTTPS web interface on the local network.
    Affected if The web interface is accessible and responds to requests.
  4. Confirm the formSetRebootTimer function exists
    Inspect the firmware binary (if accessible via telnet/SSH) for the string 'formSetRebootTimer' using 'grep -r formSetRebootTimer /' or examine the httpd binary.
    Affected if The function handler is present in the firmware.
  5. Check network exposure of the management interface
    Determine if the router's web interface is exposed to external networks (WAN) by reviewing port forwarding rules or firewall settings, or by testing remote IP access to ports 80/443.
    Affected if The management interface is reachable from untrusted networks (WAN-side).

The device is affected if it is a Tenda AX1806 router running firmware version 1.0.0.1 with the web management interface accessible, as the vulnerable formSetRebootTimer function processes the rebootTime argument without bounds checking.

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

Since the vendor has not responded to the disclosure and no patch is available, implement network-level controls such as restricting access to the router's web management interface to trusted internal IPs only, or consider replacing the device with a model that receives security updates.

Fix this in Ax1806 Firmware Scoped from the published advisory
  • Consultation4.0 h
  • Implementation6.0 h
  • Testing3.0 h
  • Review / QA2.0 h
15.0 hours of engineering $2,690
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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-2024-4239 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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