Is CVE-2026-5691 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-5691 being exploited in the wild.

How severe is CVE-2026-5691?

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-2026-5691?

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-2026-5691 attacked?

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

Am I affected by CVE-2026-5691?

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-2026-5691: Totolink A7100RU command injection in setFirewallType

CVE-2026-5691 · Severity: high · CVSS 7.3 · Published 2026-04-06

A security vulnerability exists in the Totolink A7100RU home router. This flaw allows a remote attacker to take control of the device by sending a specially crafted request to the router's management interface. Successful exploitation could lead to unauthorized access to the network, interception of data, or a complete shutdown of the device's internet services.

Technologies: TOTOLINK A7100ru. Vendors: TOTOLINK.

Quick answers

Is CVE-2026-5691 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-5691 being exploited in the wild.
How severe is CVE-2026-5691?: 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-2026-5691?: 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-2026-5691 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-5691?: 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 /cgi-bin/cstecgi.cgi component of the Totolink A7100RU router (firmware version 7.4cu.2313_b20191024). The vulnerability is located within the setFirewallType function (specifically sub_42DA2C), where the 'firewallType' parameter is improperly sanitized before being passed to the CsteSystem function and subsequently executed via execv(). A remote, unauthenticated attacker can exploit this by sending a crafted JSON POST request containing shell metacharacters (e.g., backticks) to execute arbitrary commands with system privileges. A public Proof of Concept (PoC) demonstrating the use of 'wget' via this vector has been disclosed.

Affected products

Totolink A7100RU 7.4cu.2313_b20191024

Timeline

2026-04-06: disclosed: Vulnerability and PoC publicly disclosed via GitHub and VulDB.
2026-04-06: advisory: CVE-2026-5691 published.

References

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