CVE-2026-25067

Description

SmarterTools SmarterMail versions prior to build 9518 contain an unauthenticated path coercion vulnerability in the background-of-the-day preview endpoint. The application base64-decodes attacker-supplied input and uses it as a filesystem path without validation. On Windows systems, this allows UNC paths to be resolved, causing the SmarterMail service to initiate outbound SMB authentication attempts to attacker-controlled hosts. This can be abused for credential coercion, NTLM relay attacks, and unauthorized network authentication.

CVSS breakdown

Affected products

• SmarterTools / SmarterMail0 – 100.0.9518

References

• MISChttps://www.smartertools.com/smartermail/release-notes/current
• VENDOR_ADVISORYhttps://www.vulncheck.com/advisories/smartertools-smartermail-unauthenticated-background-of-the-day-path-coercion