Actively exploited

CVE-2012-1856 Microsoft Office MSCOMCTL.OCX Remote Code Execution Vulnerability

The TabStrip ActiveX control in the Common Controls in MSCOMCTL.OCX in Microsoft Office allows remote attackers to execute arbitrary code via a crafted (1) document or (2) web page that triggers system-state corruption.

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 8.8, 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

The TabStrip ActiveX control in the Common Controls in MSCOMCTL.OCX in Microsoft Office 2003 SP3, Office 2003 Web Components SP3, Office 2007 SP2 and SP3, Office 2010 SP1, SQL Server 2000 SP4, SQL Server 2005 SP4, SQL Server 2008 SP2, SP3, R2, R2 SP1, and R2 SP2, Commerce Server 2002 SP4, Commerce Server 2007 SP2, Commerce Server 2009 Gold and R2, Host Integration Server 2004 SP1, Visual FoxPro 8.0 SP1, Visual FoxPro 9.0 SP2, and Visual Basic 6.0 Runtime allows remote attackers to execute arbitrary code via a crafted (1) document or (2) web page that triggers system-state corruption, aka "MSCOMCTL.OCX RCE Vulnerability."

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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