Actively exploited

CVE-2017-11826 Microsoft Office Remote Code Execution Vulnerability

A remote code execution vulnerability exists in Microsoft Office 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.

From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.

Our Assessment

Should You Worry?

Patch urgentlyCybergen assessment
  • CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 3 Mar 2022.
  • Rated High severity (CVSS 7.8, scored by CISA).
  • It has been in the catalogue for 1,709 days. Systems still unpatched now have almost certainly been scanned for it.
The Vulnerability

What It Is

Microsoft Office 2010, SharePoint Enterprise Server 2010, SharePoint Server 2010, Web Applications, Office Web Apps Server 2010 and 2013, Word Viewer, Word 2007, 2010, 2013 and 2016, Word Automation Services, and Office Online Server allow remote code execution when the software fails to properly handle objects in memory.

Affected Versions

ProductVersions
Microsoft Corporation Microsoft OfficeMicrosoft Office 2010, SharePoint Enterprise Server 2010, SharePoint Server 2010, Web Applications, Office Web Apps Server 2010 and 2013, Word Viewer, Word 2007, 2010, 2013 and 2016, Word Automation Services, Office Online Server.

From the public CVE record, as supplied by the vendor. Always confirm against the vendor advisory.

From Watch to Action

What To Do Now

  1. 1

    Find it

    Search your asset inventory and external attack surface for Microsoft Office. Include cloud images, appliances and anything a supplier runs for you.

    Attack Surface Management
  2. 2

    Fix it

    Apply updates per vendor instructions.

    Vulnerability Management
  3. 3

    Hunt for compromise

    If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.

    Incident Response
  4. 4

    Prove it is fixed

    Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.

    Penetration Testing

Not Sure If You Are Exposed?

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