CVE-2025-34404: MailEnable < 10.54 Reflected XSS in InstanceScope Parameter of CAL/compose.aspx

Published Dec 9, 2025
·
Updated

MailEnable versions prior to 10.54 contain a reflected cross-site scripting (XSS) vulnerability in the InstanceScope parameter of /Mondo/lang/sys/Forms/CAL/compose.aspx. The InstanceScope value is not properly sanitized when processed via a GET request and is reflected inside a <script> block in the JavaScript variable var gInstanceScope. By supplying a crafted payload that terminates the existing PageLoad() function, inserts attacker-controlled script, and comments out remaining code, a remote attacker can execute arbitrary JavaScript in a victim’s browser. Successful exploitation can redirect victims to malicious sites, steal non-HttpOnly cookies, inject arbitrary HTML or CSS, and perform actions as the authenticated user.

Affected Software

2 affected components
MailEnable MailEnable<10.54
MailEnable MailEnable<10.54

Event History

Dec 9, 2025
CVE Published
via MITRE·06:07 PM
Data Sourced
via MITRE·06:07 PM
DescriptionWeakness
Data Sourced
via NVD·06:15 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2025-34404?

CVE-2025-34404 has a high severity due to its ability to execute reflected cross-site scripting attacks.

2

How do I fix CVE-2025-34404?

To fix CVE-2025-34404, upgrade MailEnable to version 10.54 or later.

3

What is the impact of CVE-2025-34404?

The impact of CVE-2025-34404 includes potential unauthorized access to user sessions and data due to XSS exploitation.

4

Which versions of MailEnable are affected by CVE-2025-34404?

MailEnable versions prior to 10.54 are affected by CVE-2025-34404.

5

Can CVE-2025-34404 be exploited remotely?

Yes, CVE-2025-34404 can be exploited remotely via crafted GET requests containing malicious InstanceScope parameters.

Contact

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Fortitude Valley,
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info@secalerts.co
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