# CVE-2018-8349: Microsoft COM for Windows Remote Code Execution Vulnerability CVE-2018-8349 is fixed in 31 products on 1 platform, first by KB4343887, released August 14, 2018. It is not reported as exploited. Patch Radar priority: High. - Web page: https://patchblox.com/security/cve/CVE-2018-8349 - Priority: High - CVSS: 7.0 (Important) - EPSS: 0.2340 - CISA KEV: not listed - Exploited (vendor report): no - Publicly disclosed: no - Vendor exploitability assessment: Exploitation Less Likely - Published: Aug 14, 2018 - Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2018-8349 ## Description

A remote code execution vulnerability exists in "Microsoft COM for Windows" when it fails to properly handle serialized objects.

An attacker who successfully exploited the vulnerability could use a specially crafted file or script to perform actions. In an email attack scenario, an attacker could exploit the vulnerability by sending the specially crafted file to the user and convincing the user to open the file. In a web-based attack scenario, an attacker could host a website (or leverage a compromised website that accepts or hosts user-provided content) that contains a specially crafted file that is designed to exploit the vulnerability. However, an attacker would have no way to force the user to visit the website. Instead, an attacker would have to convince the user to click a link, typically by way of an enticement in an email or Instant Messenger message, and then convince the user to open the specially crafted file.

The security update addresses the vulnerability by correcting how "Microsoft COM for Windows" handles serialized objects.

## Where it's fixed | Platform | Product | Fixed in | Fix | Released | |---|---|---|---|---| | Microsoft | Windows 10 Version 1607 for 32-bit Systems | 14393.2430 | [KB4343887](https://patchblox.com/security/data/fix/microsoft/kb4343887.md) | Aug 14, 2018 | | Microsoft | Windows 10 Version 1607 for x64-based Systems | 14393.2430 | [KB4343887](https://patchblox.com/security/data/fix/microsoft/kb4343887.md) | Aug 14, 2018 | | Microsoft | Windows 10 Version 1703 for 32-bit Systems | 15063.1266 | [KB4343885](https://patchblox.com/security/data/fix/microsoft/kb4343885.md) | Aug 14, 2018 | | Microsoft | Windows 10 Version 1703 for x64-based Systems | 15063.1266 | [KB4343885](https://patchblox.com/security/data/fix/microsoft/kb4343885.md) | Aug 14, 2018 | | Microsoft | Windows 10 Version 1709 for 32-bit Systems | 16299.611 | [KB4343897](https://patchblox.com/security/data/fix/microsoft/kb4343897.md) | Aug 14, 2018 | | Microsoft | Windows 10 Version 1709 for x64-based Systems | 16299.611 | [KB4343897](https://patchblox.com/security/data/fix/microsoft/kb4343897.md) | Aug 14, 2018 | | Microsoft | Windows 10 Version 1803 for 32-bit Systems | 17134.228 | [KB4343909](https://patchblox.com/security/data/fix/microsoft/kb4343909.md) | Aug 14, 2018 | | Microsoft | Windows 10 Version 1803 for x64-based Systems | 17134.228 | [KB4343909](https://patchblox.com/security/data/fix/microsoft/kb4343909.md) | Aug 14, 2018 | | Microsoft | Windows 10 for 32-bit Systems | 10240.17946 | [KB4343892](https://patchblox.com/security/data/fix/microsoft/kb4343892.md) | Aug 14, 2018 | | Microsoft | Windows 10 for x64-based Systems | 10240.17946 | [KB4343892](https://patchblox.com/security/data/fix/microsoft/kb4343892.md) | Aug 14, 2018 | | Microsoft | Windows 7 for 32-bit Systems Service Pack 1 | | [KB4343899](https://patchblox.com/security/data/fix/microsoft/kb4343899.md) | Aug 14, 2018 | | Microsoft | Windows 7 for 32-bit Systems Service Pack 1 | | [KB4343900](https://patchblox.com/security/data/fix/microsoft/kb4343900.md) | Aug 14, 2018 | | Microsoft | Windows 7 for x64-based Systems Service Pack 1 | | [KB4343899](https://patchblox.com/security/data/fix/microsoft/kb4343899.md) | Aug 14, 2018 | | Microsoft | Windows 7 for x64-based Systems Service Pack 1 | | [KB4343900](https://patchblox.com/security/data/fix/microsoft/kb4343900.md) | Aug 14, 2018 | | Microsoft | Windows 8.1 for 32-bit systems | | [KB4343888](https://patchblox.com/security/data/fix/microsoft/kb4343888.md) | Aug 14, 2018 | | Microsoft | Windows 8.1 for 32-bit systems | | [KB4343898](https://patchblox.com/security/data/fix/microsoft/kb4343898.md) | Aug 14, 2018 | | Microsoft | Windows 8.1 for x64-based systems | | [KB4343888](https://patchblox.com/security/data/fix/microsoft/kb4343888.md) | Aug 14, 2018 | | Microsoft | Windows 8.1 for x64-based systems | | [KB4343898](https://patchblox.com/security/data/fix/microsoft/kb4343898.md) | Aug 14, 2018 | | Microsoft | Windows RT 8.1 | | [KB4343898](https://patchblox.com/security/data/fix/microsoft/kb4343898.md) | Aug 14, 2018 | | Microsoft | Windows Server 2008 R2 for Itanium-Based Systems Service Pack 1 | | [KB4343899](https://patchblox.com/security/data/fix/microsoft/kb4343899.md) | Aug 14, 2018 | | Microsoft | Windows Server 2008 R2 for Itanium-Based Systems Service Pack 1 | | [KB4343900](https://patchblox.com/security/data/fix/microsoft/kb4343900.md) | Aug 14, 2018 | | Microsoft | Windows Server 2008 R2 for x64-based Systems Service Pack 1 | | [KB4343899](https://patchblox.com/security/data/fix/microsoft/kb4343899.md) | Aug 14, 2018 | | Microsoft | Windows Server 2008 R2 for x64-based Systems Service Pack 1 | | [KB4343900](https://patchblox.com/security/data/fix/microsoft/kb4343900.md) | Aug 14, 2018 | | Microsoft | Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) | | [KB4343899](https://patchblox.com/security/data/fix/microsoft/kb4343899.md) | Aug 14, 2018 | | Microsoft | Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) | | [KB4343900](https://patchblox.com/security/data/fix/microsoft/kb4343900.md) | Aug 14, 2018 | | Microsoft | Windows Server 2008 for 32-bit Systems Service Pack 2 | | [KB4340937](https://patchblox.com/security/data/fix/microsoft/kb4340937.md) | Aug 14, 2018 | | Microsoft | Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation) | | [KB4340937](https://patchblox.com/security/data/fix/microsoft/kb4340937.md) | Aug 14, 2018 | | Microsoft | Windows Server 2008 for Itanium-Based Systems Service Pack 2 | | [KB4340937](https://patchblox.com/security/data/fix/microsoft/kb4340937.md) | Aug 14, 2018 | | Microsoft | Windows Server 2008 for x64-based Systems Service Pack 2 | | [KB4340937](https://patchblox.com/security/data/fix/microsoft/kb4340937.md) | Aug 14, 2018 | | Microsoft | Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation) | | [KB4340937](https://patchblox.com/security/data/fix/microsoft/kb4340937.md) | Aug 14, 2018 | | Microsoft | Windows Server 2012 | | [KB4343896](https://patchblox.com/security/data/fix/microsoft/kb4343896.md) | Aug 14, 2018 | | Microsoft | Windows Server 2012 | | [KB4343901](https://patchblox.com/security/data/fix/microsoft/kb4343901.md) | Aug 14, 2018 | | Microsoft | Windows Server 2012 (Server Core installation) | | [KB4343896](https://patchblox.com/security/data/fix/microsoft/kb4343896.md) | Aug 14, 2018 | | Microsoft | Windows Server 2012 (Server Core installation) | | [KB4343901](https://patchblox.com/security/data/fix/microsoft/kb4343901.md) | Aug 14, 2018 | | Microsoft | Windows Server 2012 R2 | | [KB4343888](https://patchblox.com/security/data/fix/microsoft/kb4343888.md) | Aug 14, 2018 | | Microsoft | Windows Server 2012 R2 | | [KB4343898](https://patchblox.com/security/data/fix/microsoft/kb4343898.md) | Aug 14, 2018 | | Microsoft | Windows Server 2012 R2 (Server Core installation) | | [KB4343888](https://patchblox.com/security/data/fix/microsoft/kb4343888.md) | Aug 14, 2018 | | Microsoft | Windows Server 2012 R2 (Server Core installation) | | [KB4343898](https://patchblox.com/security/data/fix/microsoft/kb4343898.md) | Aug 14, 2018 | | Microsoft | Windows Server 2016 | 14393.2430 | [KB4343887](https://patchblox.com/security/data/fix/microsoft/kb4343887.md) | Aug 14, 2018 | | Microsoft | Windows Server 2016 (Server Core installation) | 14393.2430 | [KB4343887](https://patchblox.com/security/data/fix/microsoft/kb4343887.md) | Aug 14, 2018 | | Microsoft | Windows Server, version 1709 (Server Core Installation) | 16299.611 | [KB4343897](https://patchblox.com/security/data/fix/microsoft/kb4343897.md) | Aug 14, 2018 | | Microsoft | Windows Server, version 1803 (Server Core Installation) | 17134.228 | [KB4343909](https://patchblox.com/security/data/fix/microsoft/kb4343909.md) | Aug 14, 2018 | --- Data as of 2026-11-07T18:46:35Z UTC. 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