CVE-2026-9458: Totolink A8000RU OS command injection in setWanCfg

CVE-2026-9458 · Severity: critical · CVSS 9.8 · Published 2026-05-25

A vulnerability exists in the Totolink A8000RU wireless router, a device used to provide internet connectivity and manage local networks. An attacker can remotely take full control of the router by sending a specially crafted request to its web management interface. This could lead to the theft of sensitive data, interception of network traffic, or a complete shutdown of the internet service.

Technologies: TOTOLINK A8000RU. Vendors: TOTOLINK.

Quick answers

Is CVE-2026-9458 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-9458 being exploited in the wild.
How severe is CVE-2026-9458?
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-2026-9458?
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-2026-9458 attacked?
It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-9458?
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 'setWanCfg' function of the '/cgi-bin/cstecgi.cgi' component. The vulnerability is rooted in the improper sanitization of the 'enabled' parameter, which is passed from the web interface to the 'Uci_Set_Str_By_Idx' function and eventually executed via 'execv()' through the 'CsteSystem' function. A remote, unauthenticated attacker can exploit this by sending a crafted JSON POST request containing shell metacharacters (e.g., backticks) in the 'enabled' field. Successful exploitation allows for arbitrary command execution with the privileges of the web server. A public proof-of-concept (PoC) is available.

Affected products

  • Totolink A8000RU 7.1cu.643_b20200521

Timeline

  • 2026-05-25: disclosed: Vulnerability disclosed via VulDB and NVD
  • 2026-05-25: advisory

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.