GFI MailEssentials up to 21.7 .NET Deserialization deserialization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.7$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as very critical, has been found in GFI MailEssentials up to 21.7. The affected element is an unknown function of the component .NET Deserialization. This manipulation causes deserialization. This vulnerability appears as CVE-2025-34491. The attack may be initiated remotely. There is no available exploit. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as very critical was found in GFI MailEssentials up to 21.7. Affected by this vulnerability is an unknown functionality of the component .NET Deserialization. The manipulation with an unknown input leads to a deserialization vulnerability. The CWE definition for the vulnerability is CWE-502. The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

The weakness was presented by Frycos. The advisory is shared at frycos.github.io. This vulnerability is known as CVE-2025-34491 since 04/15/2025. The exploitation appears to be easy. The attack can be launched remotely. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 05/10/2025).

Upgrading to version 21.8 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.8
VulDB Meta Temp Score: 8.7

VulDB Base Score: 8.8
VulDB Temp Score: 8.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔍

CNA Base Score: 8.8
CNA Vector (VulnCheck): 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Deserialization
CWE: CWE-502 / CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: MailEssentials 21.8

Timelineinfo

04/15/2025 🔍
04/28/2025 +13 days 🔍
04/28/2025 +0 days 🔍
05/10/2025 +12 days 🔍

Sourcesinfo

Advisory: frycos.github.io
Researcher: Frycos
Status: Confirmed

CVE: CVE-2025-34491 (🔍)
GCVE (CVE): GCVE-0-2025-34491
GCVE (VulDB): GCVE-100-306433

Entryinfo

Created: 04/28/2025 21:43
Updated: 05/10/2025 06:11
Changes: 04/28/2025 21:43 (64), 05/10/2025 06:11 (11)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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