Command InjectionWeakness · CWE-77

CVE-2026-9478

CRITICAL · 9.8 CVSS v3.1 Published 2026-05-25
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
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
A weakness has been identified in Totolink A8000RU 7.1cu.643_b20200521. Impacted is the function setParentalRules of the file /cgi-bin/cstecgi.cgi of the component Web Management Interface. Executing a manipulation of the argument enable can lead to os command injection. The attack may be performed from remote. The exploit has been made available to the public and could be used for attacks.

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

The Totolink A8000RU router firmware 7.1cu.643_b20200521 contains an OS command injection vulnerability in the web management interface CGI binary (/cgi-bin/cstecgi.cgi). The setParentalRules function improperly sanitizes the 'enable' parameter before passing it to system() or similar exec calls, allowing remote attackers to execute arbitrary operating system commands with root privileges.

MitigationApply the vendor firmware patch when available; as an interim control, disable remote web management access or place the device behind a firewall restricting HTTP/HTTPS management access to trusted IP ranges only.

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 checks

Work through these to decide whether this CVE applies to you.

  1. Confirm device model is Totolink A8000RU
    Access the router web interface or check device label/marketing materials for model number A8000RU
    Affected if Device is not a Totolink A8000RU router, then this specific CVE does not apply
  2. Check installed firmware version
    Log into the router web management interface and locate the firmware version information, typically found under System, Status, or Firmware Upgrade sections. Compare the version number to v7.1cu.643_b20200521
    Affected if Firmware version matches or is older than v7.1cu.643_b20200521 (the vulnerable version)
  3. Verify the vulnerable CGI script exists
    Attempt to access the URI /cgi-bin/cstecbi.cgi on the router (e.g., http://<router-ip>/cgi-bin/cstecbi.cgi). A 200 response or the presence of the file indicates the endpoint exists
    Affected if The /cgi-bin/cstecbi.cgi endpoint is present and accessible on the device
  4. Confirm web management interface is network-accessible
    Determine if the router web interface is reachable from network segments beyond the trusted local network, or if remote administration is enabled. Check router settings for 'Remote Management', 'Remote Access', or 'Web Management' configuration
    Affected if The web management interface is exposed to untrusted networks or remote administration is enabled, making the command injection exploitable remotely

If the device is a Totolink A8000RU running firmware version v7.1cu.643_b20200521 or earlier, the /cgi-bin/cstecbi.cgi endpoint is present, and the web management interface is accessible (especially from untrusted networks), then the environment is affected by CVE-2026-9478.

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 vendor firmware patch when available; as an interim control, disable remote web management access or place the device behind a firewall restricting HTTP/HTTPS management access to trusted IP ranges only.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation2.0 h
  • Testing6.0 h
  • Review / QA3.0 h
15.0 hours of engineering $2,600
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,160.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-9478 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-9478 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data