Cyber news

Research · Dec 28, 2025 · ZeroDay Catalog

Critical Vulnerability in SmarterMail Allows Unrestricted File Upload

A newly discovered vulnerability in SmarterTools SmarterMail could allow unauthenticated attackers to upload arbitrary files, posing a significant risk of remote code execution.

What changed

SmarterTools has identified a critical vulnerability in SmarterMail that permits unrestricted file uploads. This flaw could be exploited by unauthenticated attackers to upload malicious files to the mail server.

The potential for remote code execution makes this vulnerability particularly concerning, as it could lead to unauthorized access and control over the affected systems.

Who is affected

Organizations using SmarterTools SmarterMail are at risk due to this vulnerability. The following groups should take immediate notice:

System administrators and security teams managing email services need to be aware of the implications of this flaw.

  • SmarterTools SmarterMail users
  • Organizations relying on SmarterMail for email communications
  • IT departments responsible for maintaining email server security
  • Any entity that has deployed SmarterMail in their infrastructure

What to do

It is crucial for affected organizations to assess their current SmarterMail installations and implement necessary security measures. Immediate actions include:

Monitoring for any unusual activity on mail servers and applying security patches as they become available.

  • Review and restrict file upload permissions on the mail server
  • Implement security measures to detect and prevent unauthorized file uploads
  • Stay informed about updates from SmarterTools regarding this vulnerability
  • Conduct a thorough security audit of existing email systems

Original report

Critical Vulnerability in SmarterMail Allows Unrestricted F… · ZeroDay Findings