Stack-based Buffer OverflowWeakness · CWE-121

CVE-2026-36837

HIGH · 7.5 CVSS v3.1 Published 2026-04-29
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
TOTOLINK A3002RU V3 <= V3.0.0-B20220304.1804 was discovered to contain a stack-based buffer overflow via the hostname parameter in the formMapDelDevice function.

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 stack-based buffer overflow vulnerability exists in the hostname parameter of the formMapDelDevice function in TOTOLINK A3002RU V3 wireless router firmware (versions <= V3.0.0-B20220304.1804). The function fails to properly validate the length of user-supplied hostname input before copying it into a fixed-size stack buffer, allowing an attacker to overflow the buffer and potentially achieve code execution.

MitigationApply the latest vendor firmware update when available. Until then, restrict network access to the router's web management interface and implement network-level filtering to block unauthorized requests targeting the formMapDelDevice function.

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管理界面 and check the device information page, or use the label on the device to confirm the exact model is TOTOLINK A3002RU V3
    Affected if The model is not A3002RU V3 (other models are not affected by this specific CVE)
  2. Determine the installed firmware version
    In the router's web管理界面, navigate to System Status or Firmware Upgrade page and record the firmware version string displayed
    Affected if The firmware version is V3.0.0-B20220304.1804 or any version earlier (lower) than this release
  3. Verify web management interface accessibility
    Attempt to access the router's web interface from an untrusted network (such as the WAN/Internet) by entering the router's public IP address in a browser
    Affected if The web management interface is accessible from outside the local network without VPN or firewall restrictions
  4. Check for remote management settings
    In the router's web管理界面, go to Advanced Settings or Administration section and look for Remote Management, Web Management, or HTTP Remote Access settings
    Affected if Remote management is enabled allowing access from WAN IP addresses

You are affected if you have a TOTOLINK A3002RU V3 router running firmware version V3.0.0-B20220304.1804 or earlier AND the web management interface is accessible from untrusted networks.

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 the latest vendor firmware update when available. Until then, restrict network access to the router's web management interface and implement network-level filtering to block unauthorized requests targeting the formMapDelDevice function.

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
dbcve dependency scanner

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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-2026-36837 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
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