CVE-2025-34491

GFI MailEssentials < 21.8 MultiNode Insecure Deserialization

HIGH
8.8
CVSS Score
Published: April 28, 2025 at 07:20 PM UTC
Updated: June 17, 2026 at 09:14 AM UTC
1 product affected across 1 vendorMailessentials

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Severity
HIGH8.8
Exploit prediction
EPSS 0.9%
SSVC
PoC

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 21.8
Affected range stops below 21.8, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCPoCNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.8HIGHVulnCheck
Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-502

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