PatchSiren cyber security CVE debrief
CVE-2017-11774 Microsoft CVE debrief
CVE-2017-11774 is a Microsoft Office Outlook security feature bypass vulnerability that CISA added to its Known Exploited Vulnerabilities catalog. For defenders, the key takeaway is not exploit mechanics but urgency: systems running affected Microsoft Office/Outlook installations should be updated according to Microsoft’s guidance as soon as possible.
- Vendor
- Microsoft
- Product
- Office
- CVSS
- Unknown
- CISA KEV
- Listed
- Original CVE published
- 2021-11-03
- Original CVE updated
- 2021-11-03
- Advisory published
- 2021-11-03
- Advisory updated
- 2021-11-03
Who should care
Security and IT teams responsible for Microsoft Office and Outlook deployments, endpoint patching, email-client hardening, and vulnerability management should treat this as a priority item—especially where Outlook is broadly deployed across managed desktops or laptops.
Technical summary
The vulnerability is described in official records as an Outlook security feature bypass. The supplied corpus does not include technical root-cause detail, exploit conditions, or affected version specifics, so the safest assessment is limited to the official classification and the fact that CISA marked it as known exploited. The CISA KEV entry directs defenders to apply updates per vendor instructions.
Defensive priority
High. Inclusion in CISA’s Known Exploited Vulnerabilities catalog indicates confirmed exploitation and a need for prompt remediation.
Recommended defensive actions
- Apply Microsoft updates and mitigations per vendor instructions for affected Office/Outlook installations.
- Prioritize remediation on internet-connected and high-risk endpoints that use Outlook.
- Verify patch compliance across all managed desktops and laptops running Microsoft Office.
- Use vulnerability management and asset inventory to confirm which systems are exposed.
- Monitor for any vendor advisories or environment-specific remediation steps tied to Microsoft Office updates.
Evidence notes
CISA’s Known Exploited Vulnerabilities catalog lists this issue as “Microsoft Office Microsoft Office Outlook Security Feature Bypass Vulnerability” and includes the instruction “Apply updates per vendor instructions.” The supplied source corpus also links to the official CVE record and NVD detail page, but does not provide additional technical detail beyond the vulnerability classification and KEV status.
Sources and references
Verified primary and authoritative sources
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CVE-2017-11774 CVE Program record
Publisher, destination, and source semantics verified
URL: https://www.cve.org/CVERecord?id=CVE-2017-11774
CVE Program - Official CVE Program record with source-provided CVE metadata.
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CVE-2017-11774 NVD vulnerability detail
Publisher, destination, and source semantics verified
URL: https://nvd.nist.gov/vuln/detail/CVE-2017-11774
NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.
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CISA Known Exploited Vulnerabilities catalog
Publisher, destination, and source semantics verified
URL: https://www.cisa.gov/known-exploited-vulnerabilities-catalog
Cybersecurity and Infrastructure Security Agency - Official CISA catalog of vulnerabilities known to be exploited in the wild.
Supplemental references
-
Source item URL
Unverified legacy reference
URL: https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json
cisa_kev
Methodology and review provenance
AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.