CVE-2025-52691

CRITICAL CISA KEV

Published Dec 29, 2025 Modified Jan 27, 2026 CWE-434

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.

CVSS v3.1 Score

10.0

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

CISA Known Exploited Vulnerability

This vulnerability is actively exploited in the wild.

Added: Jan 26, 2026 Remediation due: Feb 16, 2026 Known ransomware use

Weakness Type (CWE)

CWE-434 Unrestricted Upload

Affected Products

Vendor	Product	Versions
smartertools	smartermail	< 100.0.9413

References

Exploits

https://github.com/watchtowrlabs/watchTowr-vs-SmarterMail-CVE-2025-52691?ref=labs.watchtowr.com

Other References

https://www.csa.gov.sg/alerts-and-advisories/alerts/al-2025-124/ https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-52691

Frequently Asked Questions

What is CVE-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. It has a CVSS v3.1 base score of 10.0 (CRITICAL). This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog, indicating active exploitation in the wild.

How severe is CVE-2025-52691? +

CVE-2025-52691 has a CVSS v3.1 score of 10.0 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2025-52691? +

CVE-2025-52691 affects products from smartertools, specifically: smartermail. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-52691? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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