CVE-2025-52691

Description

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.

Overview

State: PUBLISHED
Assigner (CNA): CSA
CVSS severity: CRITICAL
CVSS score: 10.0 / 10
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Effective score: 10.0 / 10 CRITICAL source: CNA overview
CWE(s): —
Reserved: 2025-06-19
Published: 2025-12-29 02:15 UTC
Last updated: 2026-02-26 16:07 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2025/52xxx/CVE-2025-52691.json
Linked Threat: CVE-2025-52691 — SmarterTools SmarterMail: SmarterTools SmarterMail Unrestricted Upload of File with Dangerous Type Vulnerability

CISA Known Exploited Vulnerabilities CISA KEV

CISA has confirmed in-the-wild exploitation of this CVE. Federal agencies must remediate by the due date below; private orgs should treat it as priority-1.

Vulnerability name: SmarterTools SmarterMail Unrestricted Upload of File with Dangerous Type Vulnerability
Vendor / project: SmarterTools
Product: SmarterMail
Date added to KEV: 2026-01-26
Remediation due: 2026-02-16
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.
Ransomware campaign use: Known
CISA notes: 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
CISA listing: www.cisa.gov/known-exploited-vulnerabilities-catalog

NVD triage scoring NVD CVE 2.0

Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.

NVD published: 2025-12-29 03:15:42 UTC
NVD last modified: 2026-01-27 15:28:07 UTC
NVD CVSS v3.1: 10.0 / 10 CRITICAL source: 5f57b9bf-260d-4433-bf07-b6a79e9bb7d4
NVD CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Exploitability subscore: 3.9 / 10
Impact subscore: 6.0 / 10
EPSS score: 0.8875 (probability of exploitation in next 30 days)
EPSS percentile: 99.53% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24

NVD-assigned CWE(s): CWE-434 (differs from the CNA list above)

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2025-205544
Assigner: CSA
Published: Dec 29, 2025, 2:15:58 AM
Updated: Feb 26, 2026, 4:07:23 PM
EUVD base score (CVSS 3.1): 10.0 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EUVD-reported EPSS: 90.1500
Vendors: SmarterTools
Products: SmarterMail (SmarterMail versions Build 9406 and earlier)
Aliases: GHSA-c9vj-8fwr-4gvq

ENISA description: 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.

EUVD references (1)

https://www.csa.gov.sg/alerts-and-advisories/alerts/al-2025-124/

Affected products (1)

Vendor	Product	Versions	Platforms
SmarterTools	SmarterMail	`SmarterMail versions Build 9406 and earlier` (affected)	—

Affected products — CPE 2.3 (1) NVD

NVD's normalized CPE 2.3 matchers, used by vendor tools (vulnerability scanners, asset managers) for automated detection. Compare with the CNA's free-text "Affected products" section above.

cpe:2.3:a:smartertools:smartermail:*:*:*:*:*:*:*:*

Vendor references (1)

References embedded in the original CVE record by the assigning CNA.

https://www.csa.gov.sg/alerts-and-advisories/alerts/al-2025-124/

Web references (4)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

http://cwe.mitre.org/data/definitions/434.html rapid7:cwe.mitre.org
https://attackerkb.com/topics/CVE-2025-52691 rapid7:attackerkb.com
https://www.csa.gov.sg/alerts-and-advisories/alerts/al-2025-124/ rapid7:www.csa.gov.sg
https://www.cve.org/CVERecord?id=CVE-2025-52691 rapid7:www.cve.org

NVD-tagged references (3)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

https://github.com/watchtowrlabs/watchTowr-vs-SmarterMail-CVE-2025-52691?ref=labs.watchtowr.com 134c704f-9b21-4f2e-91b3-4a467353bcc0 ExploitThird Party Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-52691 134c704f-9b21-4f2e-91b3-4a467353bcc0 US Government Resource
https://www.csa.gov.sg/alerts-and-advisories/alerts/al-2025-124/ 5f57b9bf-260d-4433-bf07-b6a79e9bb7d4 Third Party Advisory

Indicators (2)

IOCs linked to the auto-promoted Threat row.

Type	Value	VirusTotal	Attached
cwe	`CWE-434`	no local data	2026-05-14 02:58 UTC
cve	`CVE-2025-52691`	no local data	2026-05-14 02:58 UTC

Remediations (9)

Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.

Patch Tuesday May 2026: Security Updates & CVE Analysis

web:zecurit.com

Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .

2026-05-14 18:20 UTC
Nvd - Cve-2025-52691

web:nvd.nist.gov

An official website of the United States government NVD MENU

2026-05-14 18:20 UTC
Security Update Guide - Microsoft

web:portal.msrc.microsoft.com

The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.

2026-05-14 18:20 UTC
KB5089899 - Description of the security update for SQL Server 2025 CU4 ...

web:support.microsoft.com

Applies To SQL Server 2025 on Windows (all editions), SQL Server 2025 on Linux (all editions) Summary Improvements and fixes included in this update How to obtain and install the update How to obtain or download the latest cumulative update package for Linux More information File information Information about protection and security Summary This security update contains fixes and resolves ...

2026-05-14 18:20 UTC
Microsoft's May 2026 Patch Tuesday Fixes 130+ Vulnerabilities ...

web:windowsreport.com

Microsoft has released its May 2026 Patch Tuesday updates for Windows 11 and Windows 10, shipping as KB5089549 and KB5087544. The updates include fixes for more than 130 security vulnerabilities across Windows, Office, SharePoint, DNS components, and core system services, as Bleeping Computer writes. While no publicly disclosed zero-day vulnerabilities were reported this month, the […]

2026-05-14 18:20 UTC
Microsoft Patch Tuesday May 2026 - 120 Vulnerabilities Fixed, Including ...

web:cybersecuritynews.com

Microsoft's May 2026 Patch Tuesday lands with a heavy enterprise focus, fixing 120 vulnerabilities across Windows, Office, Azure, developer tools, and Microsoft 365 apps, including 29 remote code execution (RCE) flaws rated Critical.

2026-05-14 18:20 UTC
Dangerous Fake Microsoft Windows Update Confirmed—Do Not Download

web:www.forbes.com

As security researchers warn about a dangerous Microsoft Windows update that isn't legitimate, users must pay close attention to what they are actually downloading.

2026-05-14 18:20 UTC
Microsoft May 2026 Patch Tuesday Fixes 130+ Vulnerabilities ... - LinkedIn

web:www.linkedin.com

Microsoft has released its May 2026 Patch Tuesday security updates, addressing more than 130 vulnerabilities across its software ecosystem, including Windows, Microsoft Office, SharePoint Server ...

2026-05-14 18:20 UTC
CISA Required Action

CISA KEV

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: Known

2026-05-14 01:13 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2025-52691.json.

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