Stack-based Buffer OverflowWeakness · CWE-121

CVE-2026-36786

HIGH · 7.5 CVSS v3.1 Published 2026-06-08
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 FH451 V1.0.0.9 was discovered to contain a stack overflow in the list1 parameter of the fromDhcpListClient 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 · high confidence

Stack-based buffer overflow in Tenda FH451 router firmware V1.0.0.9 within the fromDhcpListClient function. The list1 HTTP parameter lacks proper bounds checking, allowing an attacker to overflow the stack and cause denial of service via crafted HTTP requests.

MitigationApply vendor firmware patch when available; until then, block external HTTP access to the router's web interface or implement network-level filtering to restrict malformed requests targeting the /fromDhcpListClient endpoint.

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 device model
    Access the router's web administration interface or check the device label to confirm the model is Tenda FH451
    Affected if Device is not a Tenda FH451 router, then not affected
  2. Check firmware version
    Log into the router web interface and navigate to System Status or Firmware Upgrade page to view the current firmware version; or use Nmap or curl to query the HTTP service and examine any version information in responses
    Affected if Firmware version is not V1.0.0.9 (unpatched versions are vulnerable)
  3. Confirm HTTP management interface is accessible
    Attempt to reach the router's HTTP interface on common ports 80 or 8080 using a browser or curl command: curl http://<router-ip>/
    Affected if HTTP management interface is not reachable (internal network only or disabled)
  4. Test for vulnerable parameter handling
    Send an HTTP request to the router with an abnormally long list1 parameter to the fromDhcpListClient endpoint; for example: curl -X POST http://<router-ip>/goform/fromDhcpListClient -d "list1=AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA..." (adjust endpoint path based on actual router URLs)
    Affected if Request is processed without error or rejection of oversized input, indicating the vulnerability may be present

A Tenda FH451 router running firmware V1.0.0.9 with an exposed HTTP management interface is vulnerable; the list1 parameter must be processed by the fromDhcpListClient function for exploitation.

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 patch when available; until then, block external HTTP access to the router's web interface or implement network-level filtering to restrict malformed requests targeting the /fromDhcpListClient endpoint.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation12.0 h
  • Testing6.0 h
  • Review / QA3.0 h
25.0 hours of engineering $4,400
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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-2026-36786 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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