CVE-2026-9407
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 · uneditedA security vulnerability has been detected in Totolink A8000RU 7.1cu.643_b20200521. Affected by this vulnerability is the function setFirewallType of the file /cgi-bin/cstecgi.cgi of the component Web Management Interface. The manipulation of the argument firewallType leads to os command injection. The attack is possible to be carried out remotely. The exploit has been disclosed publicly and may be used.
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 confidenceOS command injection vulnerability in Totolink A8000RU router firmware 7.1cu.643_b20200521. The setFirewallType function in /cgi-bin/cstecgi.cgi does not sanitize the firewallType parameter before passing it to system(), allowing remote attackers to execute arbitrary OS commands via the web 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
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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 checksWork through these to decide whether this CVE applies to you.
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Confirm device model is Totolink A8000RULog into the router web interface or check the device label/packaging to verify the exact model number matches A8000RUAffected if The device is a Totolink A8000RU router and is exposed to the network
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Check firmware versionIn the router web interface, navigate to System Status or Firmware Upgrade section to view the currently installed firmware versionAffected if The installed firmware version is older than the vendor fixed version (compare to Totolink's official firmware release notes)
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Verify web management interface is accessibleAttempt to access http://[router-ip]/cgi-bin/cstecfi.cgi from a browser or use curl/ wget to confirm the CGI endpoint respondsAffected if The /cgi-bin/cstecfi.cgi endpoint is reachable and responds to requests
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Confirm remote administration is enabledIn the router web interface, check the Administration or Remote Management settings to see if remote access to the web interface is enabledAffected if Remote administration is enabled and the router web interface is accessible from the WAN/internet-facing IP address
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Check network exposure of management interfacePerform an external port scan (e.g., nmap) against the public IP address of the router to detect if ports 80 or 443 (HTTP/HTTPS) are open to the internetAffected if The router's web management ports (80/443) are exposed directly to the internet without firewall protection
A defender is affected if they have a Totolink A8000RU router with an unpatched firmware version, the web management interface is accessible, and the device is network-accessible (especially from WAN).
Generated from the published advisory. Verify against your own configuration.
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 dataApply vendor firmware update if available; otherwise, disable or restrict access to the web management interface from untrusted networks, implement network segmentation, and monitor for indicators of compromise.
- Consultation6.0 h
- Implementation12.0 h
- Testing8.0 h
- Review / QA4.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $8,448.
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Free · runs locallyCheck whether your project pulls in CVE-2026-9407 — 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 sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-9407 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- 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
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