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CVE-2021-43883 is a Critical elevation of privilege vulnerability in Microsoft Windows Installer. The provided content identifies the issue by title and severity only, as part of Microsoft's December 2021 Patch Tuesday, but does not include technical details about the root cause, vulnerable code path, affected function, attack vector, or exploitation mechanism. Based on the available information, successful exploitation would allow an attacker to elevate privileges on a vulnerable Windows system through Windows Installer.
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1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos.
This repository contains a proof-of-concept (PoC) exploit for CVE-2021-43883 (a variant of CVE-2021-41379), targeting Microsoft Windows. The exploit demonstrates an arbitrary file creation/overwrite vulnerability via abuse of the Windows Installer (MSI) service. The code is written in C++ and is structured as a Visual Studio project, with main logic in 'src/main.cpp' and exploit mechanics in 'src/exploit.cpp' and supporting files. The exploit requires three user-supplied parameters: the path to a crafted MSI file, an empty install directory, and the target file path to overwrite. The PoC does not provide direct code execution (no shell), but copies its own binary into the target file to prove writability. The repository includes an example MSI project and detailed usage instructions. The attack vector is local, requiring the attacker to execute the exploit on the target system. The exploit is a simplified and more reliable version of the original InstallerFileTakeOver exploit, focusing on demonstrating the file creation primitive rather than full privilege escalation.
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2 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
An elevation of privilege vulnerability in Windows Installer.
An elevation of privilege vulnerability in Windows Installer.
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Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.