Command InjectionWeakness · CWE-77

CVE-2026-9533

MEDIUM · 6.3 CVSS v3.1 Published 2026-05-26
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
69/100
Remediation priority · Elevated
Remotely reachable 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 vulnerability was detected in Totolink CA750-PoE 6.2c.510. The impacted element is the function recvUpgradeNewFw of the file /cgi-bin/cstecgi.cgi of the component Setting Handler. Performing a manipulation of the argument fwUrl/magicid results in os command injection. It is possible to initiate the attack remotely. The exploit is now public 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 · moderate confidence

A command injection vulnerability in the recvUpgradeNewFw function of /cgi-bin/cstecgi.cgi in Totolink CA750-PoE firmware 6.2c.510 allows remote attackers to execute arbitrary OS commands by manipulating the fwUrl or magicid parameters. The vulnerability exists in the Setting Handler component of the web interface.

MitigationRestrict network access to the device's web management interface and monitor for indicators of compromise. Apply vendor firmware updates when available.

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
Low
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
Low

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

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 CA750-PoE
    Access the router web interface and check the status or system information page for the model name, or use Nmap or HTTP requests to fingerprint the device via HTTP headers or the login page.
    Affected if The device is not a Totolink CA750-PoE router
  2. Identify the installed firmware version
    Log into the router admin panel and navigate to System > Firmware Upgrade or System Status to view the firmware version. Alternatively, check the HTTP response headers or the login page source for version strings.
    Affected if The firmware version is v6.2c.510
  3. Verify the CGI endpoint /cgi-bin/cstecgi.cgi exists
    Send an HTTP GET or POST request to http://<device-ip>/cgi-bin/cstecgi.cgi and confirm the endpoint responds (even with an error). Use curl or a browser developer tools to test.
    Affected if The endpoint returns a 404 or is unreachable
  4. Check if the upgrade function is accessible via the web interface
    Navigate to the firmware upgrade or upgrade-related page in the router web interface. Look for a function that accepts a URL or ID parameter for firmware updates.
    Affected if A firmware upgrade feature accepting fwUrl or magicid parameters is present and accessible
  5. Confirm administrative access to the web interface
    Determine if the router web interface (port 80/443) is accessible from untrusted networks. Check router firewall settings, WAN access permissions, or scan the public IP for open HTTP/HTTPS ports.
    Affected if The web interface is exposed to the internet or untrusted networks without VPN restrictions

The device is affected if it is a Totolink CA750-PoE router running firmware v6.2c.510 with the /cgi-bin/cstecgi.cgi endpoint accessible, allowing unauthenticated or authenticated command injection via the firmware upgrade function.

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

Restrict network access to the device's web management interface and monitor for indicators of compromise. Apply vendor firmware updates when available.

Have this fixed Scoped from the published advisory
  • Consultation2.0 h
  • Implementation3.0 h
  • Testing2.0 h
  • Review / QA1.0 h
8.0 hours of engineering $1,420
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,272.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-9533 — 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-2026-9533 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