CVE-2026-104808: Mitel MiVoice Office 400 stored Cross-Site Scripting

Vulnerability summary

CVE-2026-104808 is a low (CVSS 1.9) vulnerability in mitel mitel mivoice office 400. EPSS estimates a 0.25% chance of exploitation in the next 30 days, higher than 16% of scored vulnerabilities.

Timeline

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

Description

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.

• CWE-79Improper Neutralization of Input During Web Page GenerationThe product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.