Is CVE-2026-9455 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-9455 being exploited in the wild.

How severe is CVE-2026-9455?

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-2026-9455?

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-2026-9455 attacked?

It is attacked over the network, in device firmware.

Am I affected by CVE-2026-9455?

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-2026-9455: Totolink A8000RU OS command injection in UploadOpenVpnCert

CVE-2026-9455 · 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 networking for homes and small offices. An attacker can exploit this flaw to take complete control of the router by sending a specially crafted request to its web management interface. This could lead to the interception of network traffic, unauthorized access to connected devices, or a total disruption of internet services.

Technologies: TOTOLINK A8000RU. Vendors: TOTOLINK.

Quick answers

Is CVE-2026-9455 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-9455 being exploited in the wild.
How severe is CVE-2026-9455?: 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-2026-9455?: 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-2026-9455 attacked?: It is attacked over the network, in device firmware.
Am I affected by CVE-2026-9455?: 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 UploadOpenVpnCert function within the /cgi-bin/cstecgi.cgi component of Totolink A8000RU firmware version 7.1cu.643_b20200521. The root cause is the improper neutralization of the 'FileName' parameter, which is passed to snprintf and subsequently executed via the CsteSystem function using execv(). A remote, unauthenticated attacker can exploit this by sending a crafted POST request containing shell metacharacters (e.g., backticks) in the FileName argument. Successful exploitation allows for arbitrary command execution with the privileges of the web server. A public exploit (PoC) has been 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-2026-9455 published.

References

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