Classic Buffer OverflowWeakness · CWE-120

CVE-2026-36809

HIGH · 7.5 CVSS v3.1 Published 2026-06-09
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
Shenzhen Tenda Technology Co., Ltd Tenda W15E v15.11.0.10 was discovered to contain a buffer overflow in the webAuthWhiteID parameter of the formModifyWebAuthWhiteUser function. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted HTTP 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 · moderate confidence

A buffer overflow vulnerability exists in the Tenda W15E router firmware v15.11.0.10 within the formModifyWebAuthWhiteUser function. The webAuthWhiteID parameter fails to perform proper bounds checking, allowing an attacker to send a crafted HTTP request with oversized data that overflows the buffer and causes denial of service.

MitigationImplement strict input validation and bounds checking on the webAuthWhiteID parameter before use in formModifyWebAuthWhiteUser. Until an official firmware patch is released, restrict administrative interface access to trusted networks or disable the web auth whitelist feature.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

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. Identify the router model
    Access the router's web interface or check the device label to confirm the model is Tenda W15E
    Affected if The device is not a Tenda W15E router
  2. Check the firmware version
    Log into the router web interface, navigate to System Settings or Status page, and locate the firmware version information. Compare it to v15.11.0.10
    Affected if The firmware version is v15.11.0.10 exactly
  3. Verify web authentication is configured
    In the router web interface, go to the Wireless or Access Control settings and check if Web Authentication (webAuthWhiteUser) feature is enabled or has white users configured
    Affected if Web authentication feature is enabled or white user entries exist
  4. Confirm web management interface accessibility
    Check if the router web management interface (HTTP/HTTPS on ports 80 or 443) is reachable from network segments that include untrusted users
    Affected if The web management interface is accessible from untrusted networks

You are affected if you own a Tenda W15E router running firmware v15.11.0.10 with the web authentication feature enabled and the management interface accessible to untrusted users.

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

Implement strict input validation and bounds checking on the webAuthWhiteID parameter before use in formModifyWebAuthWhiteUser. Until an official firmware patch is released, restrict administrative interface access to trusted networks or disable the web auth whitelist feature.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,860
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Scan for this in your stack

Free · runs locally
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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-2026-36809 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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