Actively exploited
Listed in CISA’s Known Exploited Vulnerabilities catalog since January 26, 2026.
CVE-2025-52691
SmarterTools SmarterMail Unrestricted Upload of File with Dangerous Type Vulnerability
Added to KEV January 26, 2026
Alert details
- Source feed
- CISA KEV
- CVE ID
- CVE-2025-52691
- CWE
- CWE-434
- Affected products
- SmarterMail · SmarterTools SmarterMail · SmarterTools
What happened
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.
What it means for your business
SmarterTools SmarterMail is listed in CISA's Known Exploited Vulnerabilities catalog (CVE-2025-52691). 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. CISA remediation due date: 2026-02-16. If you need help checking exposure, call (864) 335-9223.
Required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
CISA due date: February 16, 2026
Sources
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