CVE-2026-104811: Mitel MiVoice Office 400 Music on Hold WAV File Upload Code Execution

Vulnerability summary

CVE-2026-104811 is a high (CVSS 8.4) Improper Input Validation vulnerability in mitel mitel mivoice office 400. EPSS estimates a 0.21% chance of exploitation in the next 30 days, higher than 11.5% of scored vulnerabilities.

Timeline

1. 05-10-2026
   PublishedVulnerability first disclosed.
2. 05-10-2026
   Last modifiedVulnerability information updated.

Description

DigitalCanion SA has discovered a vulnerability that allows remote attackers to execute arbitrary code on affected installations of the product. Authentication may be required to exploit this vulnerability. The specific flaw exists within the Configuration → Services → Music on Hold functionality of the web portal listening on TCP port 443. The application is intended to allow users to upload WAV audio files but fails to properly validate the uploaded file type. An attacker can exploit this behavior to upload a malicious shared object (.so) instead of a WAV file. When the uploaded file is subsequently processed by the affected component, attacker-controlled code is loaded and executed in the context of the affected process. This can result in remote code execution and potentially full compromise of the underlying Linux system.

• CWE-20Improper Input ValidationThe product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.
• CWE-94Improper Control of Generation of CodeThe product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.
• CWE-434Unrestricted Upload of File with Dangerous TypeThe product allows the upload or transfer of dangerous file types that are automatically processed within its environment.
• CWE-829Inclusion of Functionality from Untrusted Control SphereThe product imports, requires, or includes executable functionality (such as a library) from a source that is outside of the intended control sphere.