Quantum Secular Labs / Blog / Advisories

CVE-2026-121609: Remote exploitation of the attack is possible.

CVE-2026-121609 is rated critical with a CVSS v3.1 base score of 10.0. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

A vulnerability was identified in Qihoo 360 Whole Home Router M5 4.0.17.1566. This issue affects the function Home of the file /etc/init.d/mpt of the component Boot Script. The manipulation leads to hard-coded credentials. Remote exploitation of the attack is possible. The exploit is publicly available and might be used. The vendor was contacted early about this disclosure but did not respond in any way.

Severity breakdown

CVSS v3.1 10.0: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

  • Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
  • Attack complexity: Low. No special conditions; the attack can be repeated reliably.
  • Privileges required: None. No account or prior access is needed.
  • User interaction: None. No action from any user is needed.
  • Scope: Changed. Impact reaches beyond the vulnerable component to other resources.
  • Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
  • Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
  • Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-259: Use of Hard-coded Password

The product contains a hard-coded password, which it uses for its own inbound authentication or for outbound authentication to external components.

CWE-798: Use of Hard-coded Credentials

The product contains hard-coded credentials, such as a password or cryptographic key.

Affected products

    References