CVE-2017-11774 Microsoft Office Outlook Security Feature Bypass Vulnerability
Microsoft Office Outlook contains a security feature bypass vulnerability due to improperly handling objects in memory. Successful exploitation allows an attacker to execute commands.
From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.
Should You Worry?
- CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 3 Nov 2021.
- Rated High severity (CVSS 7.8, scored by CISA).
- It has been in the catalogue for 1,829 days. Systems still unpatched now have almost certainly been scanned for it.
What It Is
Microsoft Outlook 2010 SP2, Outlook 2013 SP1 and RT SP1, and Outlook 2016 allow an attacker to execute arbitrary commands, due to how Microsoft Office handles objects in memory, aka "Microsoft Outlook Security Feature Bypass Vulnerability."
Affected Versions
| Product | Versions |
|---|---|
| Microsoft Corporation Microsoft Outlook | Microsoft Outlook 2010 SP2 Outlook 2013 SP1 and RT SP1 Outlook 2016 |
From the public CVE record, as supplied by the vendor. Always confirm against the vendor advisory.
What To Do Now
- 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
- 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
Prove it is fixed
Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.
Penetration Testing
Vendor Advisories
The Compliance Clock
General guidance, not legal advice. Your obligations depend on your sector, scope and jurisdiction.
Not Sure If You Are Exposed?
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