Findings

CVE-2025-34404

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.

Published Dec 9, 2025 · updated Oct 14, 2026 · mailenable mailenable

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 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.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Dec 9, 2025 · NIST NVD

    Detected

    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 block in the JavaScript variable var gInstanceScope. By supplying a crafted payload that terminates the existing PageLoad

  2. Oct 14, 2026 · NIST NVD

    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 block in the JavaScript variable var gInstanceScope. By supplying a crafted payload that terminates the existing PageLoad

Affected

  • cpe mailenable/mailenableversion unspecified

Sources

  • CVE.orgVulnerability recordCVE-2025-34404

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2025-34404

    30-day exploitation probability 0.4%

    first.org
  • NIST NVDVulnerability recordCVE-2025-34404

    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 <

    nvd.nist.gov

References