CVE-2025-34403: MailEnable < 10.54 Reflected XSS in FieldTo Parameter of AddressBook.aspx

Published Dec 9, 2025
·
Updated

MailEnable versions prior to 10.54 contain a reflected cross-site scripting (XSS) vulnerability in the FieldTo parameter of /Mondo/lang/sys/Forms/AddressBook.aspx. The FieldTo value is not properly sanitized when processed via a GET request and is reflected inside a <script> block in the JavaScript variable var fieldTo. By supplying a crafted payload that terminates the existing Finish() function, inserts attacker-controlled script, and comments out remaining code, a remote attacker can execute arbitrary JavaScript in a victim’s browser when the victim attempts to send an email. 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·06:08 PM
Data Sourced
via MITRE·06:08 PM
DescriptionWeakness
Data Sourced
via NVD·06:15 PM
DescriptionSeverityWeaknessAffected Software
Jun 20, 58335
Event
via NVD·04:26 AM

Frequently Asked Questions

1

What is the severity of CVE-2025-34403?

CVE-2025-34403 is classified as a reflected cross-site scripting (XSS) vulnerability which can lead to significant security risks, potentially allowing unauthorized access or data manipulation.

2

How do I fix CVE-2025-34403?

To mitigate CVE-2025-34403, upgrade MailEnable to version 10.54 or later where the vulnerability has been addressed.

3

What systems are affected by CVE-2025-34403?

CVE-2025-34403 affects MailEnable versions prior to 10.54.

4

What is reflected cross-site scripting as related to CVE-2025-34403?

Reflected cross-site scripting in CVE-2025-34403 occurs when unsanitized user input in the FieldTo parameter is reflected in the response, allowing attackers to inject malicious scripts.

5

Can CVE-2025-34403 lead to data theft?

Yes, CVE-2025-34403 can potentially lead to data theft as attackers may exploit the XSS vulnerability to execute scripts that steal sensitive information from users.

Contact

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