Is CVE-2026-9457 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-9457 being exploited in the wild.

How severe is CVE-2026-9457?

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-2026-9457?

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-2026-9457 attacked?

It is attacked over the network, in a network appliance.

Am I affected by CVE-2026-9457?

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.

CVE-2026-9457: Totolink A8000RU command injection in UploadFirmwareFile

CVE-2026-9457 · Severity: critical · CVSS 9.8 · Published 2026-05-25

A security vulnerability exists in the Totolink A8000RU wireless router, a device used to provide internet connectivity and local networking. 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 interception of network traffic, unauthorized access to the local network, or a total disruption of internet services.

Technologies: TOTOLINK A8000RU. Vendors: TOTOLINK.

Quick answers

Is CVE-2026-9457 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-9457 being exploited in the wild.
How severe is CVE-2026-9457?: 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-2026-9457?: 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-2026-9457 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-9457?: 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 /cgi-bin/cstecgi.cgi component. The vulnerability is located in the UploadFirmwareFile function (specifically sub_4328D0), where the 'FileName' parameter is processed using __sprintf_chk without proper sanitization before being passed to a system execution function (CsteSystem/execv). A remote, unauthenticated attacker can exploit this by sending a crafted POST request containing shell metacharacters in the FileName argument. Successful exploitation results in arbitrary command execution as the root user. Proof-of-concept code has been publicly disclosed.

Affected products

Totolink A8000RU 7.1cu.643_b20200521

Timeline

2026-05-25: disclosed: Vulnerability details and PoC published on GitHub
2026-05-25: advisory: CVE-2026-9457 published by VulDB/NVD

References

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