Risk Letters

Exploited vulnerability

CVE-2025-52691

TLP:CLEAR

SmarterTools SmarterMail Unrestricted Upload of File with Dangerous Type Vulnerability

SmarterTools SmarterMail contains an unrestricted upload of file with dangerous type vulnerability that could allow an unauthenticated attacker to upload arbitrary files to any location on the mail server, potentially enabling remote code execution.

Facts

  • Vendor: SmarterTools
  • Product: SmarterMail
  • CVSS: 10
  • EPSS (probability of exploitation within 30 days): 85.7 %
  • On CISA's Known Exploited Vulnerabilities list since: 26 January 2026
  • First known exploitation: 26 January 2026
  • Used in ransomware campaigns (per CISA): Yes
  • CISA's deadline for US federal agencies: 16 February 2026
  • Weakness: CWE-434
  • First seen by Risk Letters: 26 January 2026

Members see which Nordic sectors the flaw hits, and what to do about it.

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Data: NVD (public domain), CISA KEV, FIRST EPSS, MITRE ATT&CK, AlienVault OTX. NVD