CVE-2026-9478: Totolink A8000RU OS command injection in setParentalRules

CVE-2026-9478 · Severity: critical · CVSS 9.8 · Published 2026-05-25

A critical security vulnerability has been identified in the Totolink A8000RU wireless router, a device used to provide internet connectivity in homes and small offices. An attacker can exploit this flaw to take complete control of the router by sending a specially crafted web request. This could lead to the theft of sensitive data, interception of internet traffic, or a total disruption of network services.

Technologies: TOTOLINK A8000RU. Vendors: TOTOLINK.

Quick answers

Is CVE-2026-9478 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-9478 being exploited in the wild.
How severe is CVE-2026-9478?
Critical severity, with a CVSS score of 9.8, published 25 May 2026.
Which products and versions are affected?
TOTOLINK A8000RU 7.1cu.643_b20200521.
Is there a fix for CVE-2026-9478?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-9478 attacked?
It is attacked over the network, in device firmware.
Am I affected by CVE-2026-9478?
Check whether you run TOTOLINK A8000RU at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

An OS command injection vulnerability exists in the Totolink A8000RU router (firmware version 7.1cu.643_b20200521) within the 'setParentalRules' function of the '/cgi-bin/cstecgi.cgi' component. The vulnerability is caused by improper neutralization of the 'enable' parameter, which is passed to the 'Uci_Set_Str' function and eventually executed via 'execv()' through the 'CsteSystem' function. A remote, unauthenticated attacker can exploit this by sending a crafted POST request containing shell metacharacters (e.g., backticks) in the 'enable' field. Successful exploitation allows for full system compromise with root privileges. Public exploit code (PoC) is available.

Affected products

  • Totolink A8000RU 7.1cu.643_b20200521

Timeline

  • 2026-05-25: disclosed: Vulnerability disclosed via VulDB and GitHub PoC
  • 2026-05-25: advisory: NVD published the CVE record

References

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