I9 FirmwareOperating system · Tenda

CVE-2022-40101

HIGH · 7.5 CVSS v3.1 Published 2022-09-23
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
84/100
Remediation priority · High
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
Tenda i9 v1.0.0.8(3828) was discovered to contain a buffer overflow via the formWifiMacFilterSet function. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted string.

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

A buffer overflow vulnerability exists in the formWifiMacFilterSet function of Tenda i9 wireless router firmware v1.0.0.8(3828). The function fails to properly validate input length when processing WiFi MAC filter settings, allowing an attacker to send a crafted string that overflows a buffer and causes a Denial of Service condition.

MitigationApply vendor firmware updates when available; if no update exists, consider disabling the WiFi MAC filter feature, implementing network segmentation to limit router exposure, or deploying compensating controls such as WAF/IPS to detect exploitation attempts.

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
I9 FirmwareOperating system
Affected:= 1.0.0.8\(3828\)

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
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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. Confirm Tenda i9 router model
    Check the router label or web interface for the exact model number to verify it is a Tenda i9 device
    Affected if The device is not a Tenda i9 model, then it is not affected by this specific CVE
  2. Check firmware version
    Access the router web interface (typically at 192.168.0.1) and navigate to System Settings or Administration > Firmware Upgrade to view the installed firmware version, or check the version file via telnet/SSH if available
    Affected if The firmware version is exactly 1.0.0.8(3828), then it matches the affected version
  3. Verify WiFi MAC filter feature exists
    Log into the router web interface and locate the WiFi MAC filter settings page, typically under Wireless Settings or Advanced Wireless settings
    Affected if The MAC filter feature exists and is accessible, then the vulnerable code path is present in the firmware
  4. Check for denial of service symptoms
    If the MAC filter was recently configured, check if the router has become unresponsive, lost connectivity, or requires a reboot. Review system logs if available via the web interface or telnet/SSH
    Affected if The router exhibits unexpected crashes or unresponsiveness after MAC filter configuration, it may indicate exploitation of this buffer overflow

A Tenda i9 router running firmware version 1.0.0.8(3828) with an accessible WiFi MAC filter feature is affected by this vulnerability.

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 updates when available; if no update exists, consider disabling the WiFi MAC filter feature, implementing network segmentation to limit router exposure, or deploying compensating controls such as WAF/IPS to detect exploitation attempts.

Fix this in I9 Firmware Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA3.0 h
21.0 hours of engineering $3,680
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2022-40101 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2022-40101 in production — separate from our analysis above.

No notes yet

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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
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data