Vulnerability · CVE-2025-52691
SmarterTools SmarterMail Unrestricted Upload of File with Dangerous Type Vulnerability
Published Dec 28, 2025 · catalog updated Oct 7, 2026 · SmarterTools SmarterMail
Patch now
CVE-2025-52691 is in the CISA known-exploited catalog, due Feb 16, 2026. Confirm SmarterTools SmarterMail against the vendor advisory and apply that fix. The CVSS score does not change the priority.
Gaps on this record
- No version range is stored. A customer cannot check an installed version against this record.
- Severity
- Critical10.0
- Known exploitation
- CISA KEV and VulnCheck KEV
- EPSS
- 85.66%
- Remediation
- Remediation guidance
- Affected products
- cpe smartertools/smartermail · vendor SmarterTools SmarterMail
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. VulnCheck canary evidence. Initial-access exploit intelligence.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- cpe smartertools/smartermailversion unspecified
- vendor SmarterTools SmarterMailversion unspecified
How to fix CVE-2025-52691
Recommended remediation
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 Feb 16, 2026.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
CVE-2025-52691 is in the CISA known-exploited catalog, due Feb 16, 2026. Confirm SmarterTools SmarterMail against the vendor advisory and apply that fix. The CVSS score does not change the priority.
Which versions are affected?
Affected version ranges are not on this record. Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
What should an analyst verify?
CWE-434: Unrestricted Upload of File with Dangerous Type. EPSS 85.66%. The CISA KEV listing is the exploitation evidence. A public exploit reference is linked in Sources. That is not the same as confirmed exploitation. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Dec 28, 2025 · Catalog
Detected
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.
Jan 26, 2026 · CISA KEV
Known exploited
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Feb 16, 2026 · CISA KEV
Remediation due
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Oct 7, 2026 · Catalog
Updated
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.
Sources
- CISA KEVConfirmed exploitationCVE-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.gov - CVE.orgVulnerability recordCVE-2025-52691
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2025-52691
30-day exploitation probability 85.7%
first.org - Metasploit ModulesPublic exploit moduleexploit_multi/http/smartermail_guid_file_upload
Public module reference (excellent). Module source is not copied into this catalog.
rapid7.com - NIST NVDVulnerability recordCVE-2025-52691
Successful exploitation of the vulnerability could allow an unauthenticated attacker to upload arbitrary files to any location on the mail server, potentially enabling remote code execution.
nvd.nist.gov - VulnCheck KEVConfirmed exploitationCVE-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.
vulncheck.com
References
- VulnCheck exploitation evidence · api.vulncheck.com
- VulnCheck exploitation evidence · fortiguard.fortinet.com
- Exploit · github.com
- VulnCheck exploitation evidence · labs.watchtowr.com
- CISA note · nvd.nist.gov
- US Government Resource · cisa.gov
- VulnCheck exploitation evidence · cisa.gov
- CISA note · csa.gov.sg
- VulnCheck exploitation evidence · huntress.com
- VulnCheck exploitation evidence · recordedfuture.com
- CISA note · smartertools.com
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.