CVE-2026-104808: Mitel MiVoice Office 400 stored Cross-Site Scripting
DigitalCanion has discovered a stored Cross-Site Scripting (XSS) vulnerability that allows an authenticated malicious user to inject persistent JavaScript or HTML content, resulting in a denial-of-service condition within the web application.
The specific flaw exists within the web portal listening on TCP port 443, under Configuration → Users → Users List. The vulnerability occurs in the “Microsoft Exchange mailbox” field, which fails to properly validate or sanitize user-supplied input before storing and rendering it.
By injecting malicious JavaScript into this field, an attacker can cause the payload to execute whenever the affected user properties are accessed. This can prevent access to the affected user properties and result in a denial-of-service condition within the application's user-management functionality.
Affected Software
Event History
Frequently Asked Questions
Who can exploit this issue?
An attacker must be authenticated to the MiVoice Office 400 web portal and able to modify entries under Configuration → Users → Users List, specifically the “Microsoft Exchange mailbox” field.
When does the injected content execute?
The stored JavaScript or HTML executes when the affected user properties are accessed. This can make those user properties inaccessible and disrupt user-management functions.
Is the default configuration affected?
The available information does not state whether the vulnerable user-management functionality or the required permissions are present in a default configuration.