CVE-2025-34491

HIGH

GFI Mailessentials < 21.8 - Insecure Deserialization

Title source: rule

Description

GFI MailEssentials prior to version 21.8 is vulnerable to a .NET deserialization issue. A remote and authenticated attacker can execute arbitrary code by sending crafted serialized .NET when joining to a Multi-Server setup.

References (3)

[Exploit] https://frycos.github.io/vulns4free/2025/04/28/mailessentials.html

[Release Notes] https://gfi.ai/products-and-solutions/network-security-solutions/mailessentials/resources/documentation/product-releases

[Third Party Advisory] https://www.vulncheck.com/advisories/gfi-mailessentials-multinode-insecure-deserialization

Scores

CVSS v3 8.8

EPSS 0.0116

EPSS Percentile 78.4%

Attack Vector NETWORK

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

Classification

CWE

CWE-502

Status published

Affected Products (1)

gfi/mailessentials < 21.8

Timeline

Published Apr 28, 2025

Tracked Since Feb 18, 2026