A remote code execution vulnerability exists in Microsoft Excel software when the software fails to properly handle objects in memory. An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the current user. If the current user is logged on with administrative user rights, an attacker could take control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
Exploitation of the vulnerability requires that a user open a specially crafted file with an affected version of Microsoft Excel. 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) containing a specially crafted file designed to exploit the vulnerability. An attacker would have no way to force users to visit the website. Instead, an attacker would have to convince users to click a link, typically by way of an enticement in an email or instant message, and then convince them to open the specially crafted file.
The security update addresses the vulnerability by correcting how Microsoft Excel handles objects in memory.
## Where it's fixed | Platform | Product | Fixed in | Fix | Released | |---|---|---|---|---| | Microsoft | Microsoft Excel 2010 Service Pack 2 (32-bit editions) | | [KB4461577](https://patchblox.com/security/data/fix/microsoft/kb4461577.md) | Dec 11, 2018 | | Microsoft | Microsoft Excel 2010 Service Pack 2 (64-bit editions) | | [KB4461577](https://patchblox.com/security/data/fix/microsoft/kb4461577.md) | Dec 11, 2018 | | Microsoft | Microsoft Excel 2013 RT Service Pack 1 | | [KB4461559](https://patchblox.com/security/data/fix/microsoft/kb4461559.md) | Dec 11, 2018 | | Microsoft | Microsoft Excel 2013 Service Pack 1 (32-bit editions) | | [KB4461559](https://patchblox.com/security/data/fix/microsoft/kb4461559.md) | Dec 11, 2018 | | Microsoft | Microsoft Excel 2013 Service Pack 1 (64-bit editions) | | [KB4461559](https://patchblox.com/security/data/fix/microsoft/kb4461559.md) | Dec 11, 2018 | | Microsoft | Microsoft Excel 2016 (32-bit edition) | | [KB4461542](https://patchblox.com/security/data/fix/microsoft/kb4461542.md) | Dec 11, 2018 | | Microsoft | Microsoft Excel 2016 (64-bit edition) | | [KB4461542](https://patchblox.com/security/data/fix/microsoft/kb4461542.md) | Dec 11, 2018 | | Microsoft | Microsoft Office 2010 Service Pack 2 (32-bit editions) | | [KB4461570](https://patchblox.com/security/data/fix/microsoft/kb4461570.md) | Dec 11, 2018 | | Microsoft | Microsoft Office 2010 Service Pack 2 (64-bit editions) | | [KB4461570](https://patchblox.com/security/data/fix/microsoft/kb4461570.md) | Dec 11, 2018 | | Microsoft | Microsoft Office Compatibility Pack Service Pack 3 | | [KB4461565](https://patchblox.com/security/data/fix/microsoft/kb4461565.md) | Dec 11, 2018 | --- Data as of 2026-11-07T18:46:35Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.