Is CVE-2026-5678 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-5678 being exploited in the wild.

How severe is CVE-2026-5678?

High severity, with a CVSS score of 7.3, published 6 April 2026.

Which products and versions are affected?

TOTOLINK A7100ru 7.4cu.2313_b20191024.

Is there a fix for CVE-2026-5678?

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-2026-5678 attacked?

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

Am I affected by CVE-2026-5678?

Check whether you run TOTOLINK A7100ru 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-2026-5678: Totolink A7100RU OS command injection in cstecgi.cgi

CVE-2026-5678 · Severity: high · CVSS 7.3 · Published 2026-04-06

The Totolink A7100RU router, a device used for home and small office networking, contains a security flaw that allows unauthorized remote users to take control of the device. By sending a specially crafted request to the router's management interface, an attacker can execute system-level commands. This could lead to a complete compromise of the network traffic, unauthorized access to connected devices, or a total service outage.

Technologies: TOTOLINK A7100ru. Vendors: TOTOLINK.

Quick answers

Is CVE-2026-5678 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-5678 being exploited in the wild.
How severe is CVE-2026-5678?: High severity, with a CVSS score of 7.3, published 6 April 2026.
Which products and versions are affected?: TOTOLINK A7100ru 7.4cu.2313_b20191024.
Is there a fix for CVE-2026-5678?: 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-2026-5678 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-5678?: Check whether you run TOTOLINK A7100ru 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 A7100RU router (firmware version 7.4cu.2313_b20191024) within the /cgi-bin/cstecgi.cgi component. The vulnerability is located in the setScheduleCfg function (specifically sub_42E7D8), which fails to properly sanitize the user-provided 'mode' parameter. This parameter is passed to Uci_Set_Str and subsequently formatted into a command string via snprintf before being executed by 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 'mode' field to achieve arbitrary code execution. A public proof-of-concept (PoC) demonstrating the use of wget for command execution has been disclosed.

Affected products

Totolink A7100RU 7.4cu.2313_b20191024

Timeline

2026-04-06: disclosed
2026-04-06: advisory

References

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