Stack-based Buffer OverflowWeakness · CWE-121

CVE-2026-36770

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 US_W3V1.0BR v1.0.0.3 was discovered to contain a stack overflow in the Go parameter of the ask_to_reboot function. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted input.

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 buffer overflow vulnerability exists in the Tenda US_W3V1.0BR router firmware v1.0.0.3. The vulnerability is in the 'ask_to_reboot' function where the 'Go' parameter is not properly validated before being copied to a stack-based buffer, allowing an attacker to overflow the stack and cause a Denial of Service.

MitigationImplement proper input validation and bounds checking on the 'Go' parameter before copying to the stack buffer. If available, apply vendor firmware updates. As a temporary workaround, restrict access to the affected management interface.

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 administration interface or check the device label/marketing to confirm the model is Tenda US_W3V1.0BR
    Affected if The device is a Tenda US_W3V1.0BR router
  2. Check the firmware version
    Log into the router's web interface (typically at 192.168.0.1 or 192.168.1.1) and navigate to System Settings or Status page to view the firmware version; alternatively, check via telnet/SSH if enabled
    Affected if The firmware version is 1.0.0.3 (exact match to the affected version)
  3. Verify the ask_to_reboot endpoint exists
    Send a GET request to common Tenda endpoints (such as /goform/ or /cgi/) to enumerate available forms and identify if ask_to_reboot is exposed; this typically appears as /goform/ask_to_reboot
    Affected if The /goform/ask_to_reboot endpoint is accessible via HTTP/HTTPS without authentication
  4. Confirm the Go parameter is accepted
    Send a POST request to the ask_to_reboot endpoint with a test 'Go' parameter value (such as 'test') and observe if the parameter is processed without sanitization errors
    Affected if The router accepts and processes the 'Go' parameter without rejecting unusual input

A user is affected if they own a Tenda US_W3V1.0BR router running firmware version 1.0.0.3 with the ask_to_reboot web endpoint publicly or internally accessible.

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 proper input validation and bounds checking on the 'Go' parameter before copying to the stack buffer. If available, apply vendor firmware updates. As a temporary workaround, restrict access to the affected management interface.

Have this fixed Scoped from the published advisory
  • Consultation3.0 h
  • Implementation8.0 h
  • Testing4.0 h
  • Review / QA2.0 h
17.0 hours of engineering $3,000
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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-2026-36770 in production — separate from our analysis above.

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