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Mallory
HighPublic exploit

.NET Framework COM object activation elevation of privilege (CVE-2020-1066)

IdentifiersCVE-2020-1066CWE-269

An elevation of privilege vulnerability in Microsoft .NET Framework related to incorrect handling of COM object activation. An attacker who already has the ability to execute code on the local machine can run a specially crafted/malicious program to exploit the flaw and elevate privileges. Microsoft’s fix is described as correcting how .NET Framework activates COM objects. Also known as “.NET Framework Elevation of Privilege Vulnerability.”

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation allows local elevation of privilege on the affected system, enabling an attacker to execute with higher privileges than intended (potentially up to SYSTEM depending on context), facilitating follow-on actions such as disabling security controls, credential access, and broader compromise workflows.

Mitigation

If you can’t patch tonight, do this now.

No specific mitigations are provided in the supplied content beyond patching. As a practical mitigation, reduce opportunities for local code execution by untrusted users and restrict local access where possible until updates are applied.

Remediation

Patch, then assume compromise.

Apply Microsoft’s security update for CVE-2020-1066 that corrects .NET Framework COM object activation behavior.
PUBLIC EXPLOITS

Exploits

1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos.

VALID 1 / 1 TOTALView more in app
CVE-2020-1066-EXPMaturityPoCVerified exploit

This repository contains a full exploit for CVE-2020-1066, a local privilege escalation vulnerability in Microsoft Windows 7 and Windows Server 2008 R2. The vulnerability exists in the Windows CardSpace (idsvc) service, which runs as SYSTEM and exposes an RPC interface. The exploit abuses improper handling of symbolic links and hardlinks by the service when moving files in the user's %APPDATA% directory, allowing a local attacker to replace arbitrary files with SYSTEM privileges. The repository is structured as a Visual Studio solution with three main components: - CommonUtils: Utility library for file, symlink, hardlink, and registry manipulation, as well as privilege management. - MyComDefine: Contains the MIDL-generated RPC interface definitions and stubs for communicating with the CardSpace service. - MyComEop: The main exploit executable, which orchestrates the attack by creating symlinks, hardlinks, and mount points, and then triggering the vulnerable CardSpace RPC operations to replace target files and escalate privileges. The exploit is highly configurable, allowing the user to specify which file to replace (default is System.EnterpriseServices.tlb), which COM interface or TypeLib to target, and even to execute arbitrary commands as SYSTEM. The README provides detailed background, usage instructions, and references to related projects and the official CVE advisory. The attack vector is local, requiring code execution as a regular user, but does not require administrator privileges. The exploit demonstrates advanced file system manipulation techniques and direct interaction with Windows RPC and COM subsystems.

cbwang505Disclosed Jun 1, 2020c++idllocal
EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType
Microsoft Corporation.Net Frameworkapplication

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

What this page doesn’t show

The version that knows your environment.

This page is what’s public. Mallory adds the parts that aren’t: which of your assets are affected, which adversaries are exploiting it right now, which detections to deploy, and what to do tonight.
Exposure mapping

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Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware1

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity2

Community discussion across Reddit, Mastodon, and other social sources.