dbcve.org
MailenableApplication

CVE-2025-34399

MEDIUM · 6.1 CVSS v3.1 Published 2025-12-09
Fix available
A fix is available. Upgrade to 10.54 or later.
See remediation →
68/100
Remediation priority · Elevated
Remotely reachable No privileges

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
MailEnable versions prior to 10.54 contain a reflected cross-site scripting (XSS) vulnerability in the AddressesCc parameter of /Mondo/lang/sys/Forms/AddressBook.aspx. The AddressesCc value is not properly sanitized when processed via a GET request and is reflected within a <script> block in the JavaScript variable var sAddrCc. By supplying a crafted payload that terminates the existing LoadCurAddresses() 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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

MailEnable versions before 10.54 have a reflected XSS vulnerability in the AddressesCc parameter of /Mondo/lang/sys/Forms/AddressBook.aspx. The parameter value from a GET request is directly reflected into a JavaScript variable (sAddrCc) inside a <script> block without sanitization, allowing attackers to inject arbitrary JavaScript by terminating the existing function and commenting out remaining code.

MitigationUpgrade to MailEnable version 10.54 or later. Until patched, sanitize all user-supplied input in the AddressesCc parameter using context-aware output encoding before reflecting it into HTML or JavaScript contexts.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
MailenableApplication
Affected:< 10.54

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Confirm MailEnable installation
    Locate MailEnable installation directory (typically C:\Program Files\MailEnable or C:\Program Files (x86)\MailEnable) or check Windows Services for 'MailEnable Service' entry.
    Affected if MailEnable is not installed on the system.
  2. Identify MailEnable version
    Check the MailEnable version by opening the MailEnable Administrator, going to the General > About section, or examining the version info of MEAdmin.exe or MailEnable.exe in the installation directory.
    Affected if The installed version is earlier than 10.54 (e.g., 10.53, 10.52, etc.).
  3. Verify vulnerable endpoint exists
    Attempt to access the path /Mondo/lang/sys/Forms/AddressBook.aspx via the web server (e.g., http://<hostname>/Mondo/lang/sys/Forms/AddressBook.aspx). This is the vulnerable ASPX page.
    Affected if The AddressBook.aspx page returns a 200 OK response, indicating the page is accessible.
  4. Test AddressesCc parameter reflection
    Send a GET request to the AddressBook.aspx page with a test value in the AddressesCc parameter (e.g., ?AddressesCc=test), then inspect the response HTML to see if the value appears inside a <script> block unescaped.
    Affected if The AddressesCc parameter value is reflected directly into the page source without HTML or JavaScript encoding (e.g., the value appears as raw text in sAddrCc variable).

The environment is affected if MailEnable version is below 10.54 AND the /Mondo/lang/sys/Forms/AddressBook.aspx endpoint is accessible and reflects the AddressesCc parameter without sanitization.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 10.54 or later
Fixed in 10.54
Interim mitigation

Upgrade to MailEnable version 10.54 or later. Until patched, sanitize all user-supplied input in the AddressesCc parameter using context-aware output encoding before reflecting it into HTML or JavaScript contexts.

Recommended fix High confidence

10.54

  1. 1. Obtain MailEnable version 10.54 or later from the official MailEnable download site (mailenable.com or www.mailenable.com).
  2. 2. Before upgrading, back up the current MailEnable configuration and data directories.
  3. 3. Apply the upgrade to the MailEnable installation.
  4. 4. After upgrading, verify the version number matches 10.54 or later.
  5. 5. Test the /Mondo/lang/sys/Forms/AddressBook.aspx page with a normal request to confirm functionality works.
  6. 6. Consider setting the AddressesCc parameter to be rejected or sanitized at a web application firewall (WAF) level as an additional defense-in-depth measure until the upgrade is applied.

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Mailenable Scoped from the published advisory
  • Consultation2.0 h
  • Implementation3.0 h
  • Testing2.0 h
  • Review / QA1.0 h
8.0 hours of engineering $1,420
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,272.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2025-34399 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-34399 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data