Microsoft Office Word: Information disclosure via uninitialized resource
Summary
Microsoft Office Word contains a use of uninitialized resource flaw (CWE-908) that allows an unauthorized attacker to disclose information over a network. According to the CVSS vector, a user must interact, typically by opening a crafted document. The impact is high confidentiality loss with no integrity or availability impact, and the sources checked report no exploitation.
Affected
- Microsoft 365 Apps for Enterprise: 16.0.1 before the fixed build (not stated in the CNA record)
- Office 365 for Mac: 1.0.0 before 16.115.26110837
- Office LTSC 2021: 16.0.1 before 16.0.14334.21048
- Office LTSC 2024: 16.0.0 before 16.0.17932.21140 (unconfirmed, only in third-party tracker)
- Office LTSC for Mac 2021 and 2024: before 16.115.26110837 (LTSC for Mac 2024 unconfirmed)
Fixed in
- Office LTSC 2021: 16.0.14334.21048 or later
- Office 365 for Mac: 16.115.26110837 or later
- Microsoft 365 Apps for Enterprise: fixed build not stated; check the MSRC advisory
- Fix released with the Word updates of November 10, 2026
Workaround
Unknown.
Exploitation
- No exploitation in the wild found in the sources checked.
- CVSS vector E:U: no known working exploit code.
- No public proof of concept found.
- NVD status at publication: Awaiting Analysis.
Our recommendation
- Deploy the November 10, 2026 Office/Word security update to all Microsoft 365 Apps, Office LTSC and Office for Mac clients.
- Verify installed builds against the fixed versions in the MSRC advisory.
- Prioritise patching where confidential or client data is processed in Word.
- Monitor NVD and CISA KEV for changes in exploitation status.
Information from Microsoft (Patch Tuesday November 2026)
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Response Center advisory CVE-2026-116721 msrc.microsoft.com
- CVE Record CVE-2026-116721 (CVE Program) www.cve.org
- Microsoft 365 Apps security updates (Microsoft Learn) learn.microsoft.com
- Zero Day Initiative November 2026 security update review www.zerodayinitiative.com
- Strix CVE tracker entry CVE-2026-116721 www.strix.ai
- GBHackers Microsoft November 2026 Patch Tuesday gbhackers.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, 12:17.
Original description (NVD)
Use of uninitialized resource in Microsoft Office Word 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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