CVE-2025-52691 (GCVE-0-2025-52691)

Vulnerability from cvelistv5 – Published: 2025-12-29 02:15 – Updated: 2026-02-26 16:07
VLAI CISA Previdian
Title
Upload Arbitrary Files
Summary
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.
Severity
10 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
SSVC
Exploitation: active Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-27 04:55 UTC
CWE
  • CWE-434 - Unrestricted Upload of File with Dangerous Type
Assigner
References
Impacted products
Vendor Product Version
SmarterTools SmarterMail Affected: SmarterMail versions Build 9406 and earlier
Create a notification for this product.
Date Public
2025-12-29 02:11
Credits
Chua Meng Han
CISA
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: a596b19b-3e0c-417b-bd19-0a33c74efd74

Vulnerability ID: CVE-2025-52691

Status: Confirmed

Status Updated: 2026-01-26 01:00 CET

Exploited: Yes

Timestamps
First Seen: 2026-01-26
Asserted: 2026-01-26
Scope
Notes: SmarterTools SmarterMail Unrestricted Upload of File with Dangerous Type Vulnerability | Affected: SmarterTools / SmarterMail | Description: 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. | 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. | Due date: 2026-02-16 | Known ransomware campaign use (KEV): Known | Notes (KEV): https://www.smartertools.com/smartermail/release-notes/current ; https://www.csa.gov.sg/alerts-and-advisories/alerts/al-2025-124/ ; https://nvd.nist.gov/vuln/detail/CVE-2025-52691
Evidence

Type: Vendor Report

Signal: Successful Exploitation

Confidence: 80%

Source: cisa-kev

Details
Cwes CWE-434
Feed CISA Known Exploited Vulnerabilities Catalog
Product SmarterMail
Due Date 2026-02-16
Date Added 2026-01-26
Vendorproject SmarterTools
Vulnerabilityname SmarterTools SmarterMail Unrestricted Upload of File with Dangerous Type Vulnerability
Knownransomwarecampaignuse Known
References
Created: 2026-10-02 08:09 CEST | Updated: 2026-10-02 08:09 CEST
Previdian
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: fb92ecf6-6431-4065-9aa7-d866ddfe24f6

Vulnerability ID: CVE-2025-52691

Status: Confirmed

Status Updated: 2026-06-01 12:49 CEST

Exploited: Yes

Timestamps
First Seen: 2026-06-01
Asserted: 2026-06-01
Scope
Notes: Upload Arbitrary Files | Affected: SmarterTools / SmarterMail | CVSS: 10.0 (CRITICAL) | EPSS: 0.85655 | Used in malware: yes | Listed 1 day ahead of CISA KEV | Not yet in CISA KEV: False
Evidence

Type: Public Report

Signal: Confirmed Compromise

Confidence: 70%

Source: previdian

Details
Feed Previdian (previdian.com)
Title Upload Arbitrary Files
Cve Id CVE-2025-52691
Vendor SmarterTools
Ghsa Id None
Product SmarterMail
Added Date 2026-06-01T10:49:47.987Z
Cvss Score 10.0
Epss Score 0.85655
Previous Ids
Cvss Severity CRITICAL
Virtual Patch False
Cvss Estimated False
Epss Percentile 0.99719
Used In Malware yes
Vulnerability Id CVE-2025-52691
Ahead Of Cisa Kev 
{
  "count": 1,
  "unit": "day"
}
Not Yet In Cisa Kev False
References
Created: 2026-10-02 09:09 CEST | Updated: 2026-10-02 09:09 CEST
Show details on NVD website
To clipboard 

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Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

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