Microsoft Office Outlook: Information disclosure through type confusion
Summary
A type confusion flaw in Microsoft Office Outlook allows an unauthenticated remote attacker to disclose information over the network. Exploitation requires that a user interacts with a crafted message, for example by opening it. According to the CVSS vector, only confidentiality is affected. The vendor advisory could not be verified directly, and exploitation is not confirmed for this CVE.
Affected
- Microsoft 365 Apps for Enterprise: 16.0.1 up to the fixed build listed on https://aka.ms/OfficeSecurityReleases (exact build unknown)
- Office LTSC 2021: 16.0.1 before 16.0.14334.21048
- Office LTSC 2024: 16.0.0 before 16.0.17932.21140 (build from third-party mirror, verify with MSRC)
Fixed in
- Office security update released on November 10, 2026 (listed under Outlook in Microsoft release notes)
- Office LTSC 2021: 16.0.14334.21048 or later
- Office LTSC 2024: 16.0.17932.21140 or later (unverified)
- Microsoft 365 Apps for Enterprise: fixed build unknown
Workaround
Unknown. No workaround is documented in the sources; patching is the only known remedy.
Exploitation
- Not known to be exploited in the wild according to Rapid7
- No public proof of concept found
- Not listed in CISA KEV according to the sources consulted
- Do not confuse with CVE-2026-124194, a separate exploited Outlook flaw
Our recommendation
- Install the November 10, 2026 Office security update on all Outlook and Office clients as a priority
- Verify the fixed build numbers in the MSRC Security Update Guide before rollout
- Remind users not to open unexpected or suspicious emails and attachments
- Monitor for updates to the advisory and to exploitation reports
Information from Microsoft (Patch Tuesday November 2026)
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- CVE.org record CVE-2026-119993 www.cve.org
- MSRC Security Update Guide msrc.microsoft.com
- Microsoft 365 Apps security updates learn.microsoft.com
- Rapid7 November 2026 Patch Tuesday www.rapid7.com
- Strix CVE-2026-119993 (secondary) www.strix.ai
- ThreatInt CVE-2026-119993 (secondary) cve.threatint.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 11 Nov 2026, 12:05.
Original description (NVD)
Access of resource using incompatible type ('type confusion') in Microsoft Office Outlook allows an unauthorized attacker to disclose information over a network.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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