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Status published
High
CVE-2025-34491
GFI MailEssentials < 21.8 MultiNode Insecure Deserialization
Vulnerability 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.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:
- Frycos
References
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Affected Vendor
Affected Software
MailEssentials
Vulnerable Versions:
0
Timeline
Official Publish:
April 28th, 2025
Last Modified:
November 19th, 2025
Added to House:
July 22nd, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H