CVE-2020-17144

HIGH KEV

Microsoft Exchange Server - Remote Code Execution via Untrusted Data Deserialization

Title source: llm
STIX 2.1

Exploitation Summary

CVE-2020-17144 is actively exploited and listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added November 3, 2021. EIP tracks 5 public exploits from researchers including zcgonvh, Airboi, delete_user.

AI-analyzed exploit summary This exploit leverages a .NET deserialization vulnerability in Microsoft Exchange Server 2010 (CVE-2020-17144) to achieve remote code execution by crafting a malicious payload and saving it as a UserConfiguration object. The payload uses a complex chain of LINQ enumerators and reflection to trigger arbitrary code execution when deserialized.

Description

Microsoft Exchange Remote Code Execution Vulnerability

Exploits (5)

nomisec WORKING POC 159 stars
by zcgonvh · remote-auth
https://github.com/zcgonvh/CVE-2020-17144

This exploit leverages a .NET deserialization vulnerability in Microsoft Exchange Server 2010 (CVE-2020-17144) to achieve remote code execution by crafting a malicious payload and saving it as a UserConfiguration object. The payload uses a complex chain of LINQ enumerators and reflection to trigger arbitrary code execution when deserialized.

Classification
Working Poc 95%
Attack Type
Rce
Complexity
Complex
Reliability
Reliable
Target: Microsoft Exchange Server 2010
Auth required
Prerequisites: Valid credentials for Exchange Server · Network access to the Exchange Server · A malicious DLL (e.dll) to be loaded
devstral-2 · analyzed Feb 16, 2026 Full analysis →
nomisec WORKING POC 157 stars
by Airboi · remote-auth
https://github.com/Airboi/CVE-2020-17144-EXP

This is a functional exploit for CVE-2020-17144, targeting Microsoft Exchange Server via deserialization. It leverages ysoserial.net to generate a malicious payload that writes a webshell to the Exchange Server's autodiscover directory.

Classification
Working Poc 95%
Attack Type
Rce
Complexity
Moderate
Reliability
Reliable
Target: Microsoft Exchange Server (likely 2010, given the EWS endpoint)
Auth required
Prerequisites: Valid credentials for the target Exchange Server · Network access to the EWS endpoint · .NET environment for compilation
devstral-2 · analyzed Feb 16, 2026 Full analysis →
patchapalooza WORKING POC
by delete_user · poc
https://gitee.com/delete_user/CVE-2020-17144-EXP

This repository contains a functional exploit for CVE-2020-17144, leveraging a .NET deserialization vulnerability in Exchange Server 2010. The exploit uses ysoserial.net to generate a malicious payload that achieves remote code execution by exploiting the BinaryFormatter deserialization chain.

Classification
Working Poc 95%
Attack Type
Deserialization
Complexity
Moderate
Reliability
Reliable
Target: Microsoft Exchange Server 2010
Auth required
Prerequisites: valid Exchange 2010 credentials · network access to the target server
devstral-2 · analyzed Feb 23, 2026 Full analysis →
patchapalooza WORKING POC
by delete_user · poc
https://gitee.com/delete_user/CVE-2020-17144

This repository contains a functional exploit for CVE-2020-17144, a deserialization vulnerability in Microsoft Exchange 2010. The exploit leverages unsafe deserialization in the MRM.AutoTag.Model component to achieve remote code execution by creating a malicious UserConfiguration object.

Classification
Working Poc 95%
Attack Type
Rce
Complexity
Moderate
Reliability
Reliable
Target: Microsoft Exchange 2010
Auth required
Prerequisites: valid credentials for the target Exchange server · .NET Framework 3.5
devstral-2 · analyzed Feb 23, 2026 Full analysis →
patchapalooza WORKING POC
by h1d3r · poc
https://gitee.com/h1d3r/CVE-2020-17144

This repository contains a functional exploit for CVE-2020-17144, a Microsoft Exchange 2010 MRM.AutoTag.Model unsafe deserialization vulnerability. The exploit leverages a crafted payload to achieve remote code execution by creating a malicious UserConfiguration object.

Classification
Working Poc 95%
Attack Type
Rce
Complexity
Moderate
Reliability
Reliable
Target: Microsoft Exchange 2010
Auth required
Prerequisites: valid credentials for the target Exchange server · .NET Framework 3.5
devstral-2 · analyzed Feb 23, 2026 Full analysis →

Scores

CVSS v3 8.4
EPSS 0.3665
EPSS Percentile 98.3%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation active
Automatable yes
Technical Impact total

Details

CISA KEV 2021-11-03
VulnCheck KEV 2021-11-03
InTheWild.io 2021-07-23
ENISA EUVD EUVD-2020-9098
CWE
CWE-502
Status published
Products (2)
microsoft/exchange_server 2010 sp3_rollup_31
Microsoft/Microsoft Exchange Server 2010 Service Pack 3 Update Rollup 31 < publication
Published Dec 10, 2020
KEV Added Nov 03, 2021
Tracked Since Feb 18, 2026