Microsoft Office Word: Use after free allows remote code execution
Summary
A use-after-free vulnerability (CWE-416) in Microsoft Office Word allows an unauthenticated remote attacker to execute code. The victim must open a crafted Word document, for example one received by email or download. Microsoft rates it Important, and no exploitation is known at the time of publication.
Affected
- Microsoft 365 Apps for Enterprise (versions from 16.0.1, see Microsoft's Office security release page for the fixed build)
- Office 365 for Mac: 1.0.0 to before 16.115.26110837
- Office LTSC for Mac 2021: 16.0.1 to before 16.115.26110837
- Office LTSC for Mac 2024: 16.0.0 to before 16.115.26110837
- Windows Microsoft 365 Apps and Windows Office LTSC 2021/2024: not listed in the CNA data, unknown
Fixed in
- Mac builds: 16.115.26110837 or later (per CNA data)
- Microsoft 365 Apps: November 2026 Office update, exact build unknown
- Windows Office LTSC: fixed builds unknown, to be confirmed on MSRC
Workaround
- No vendor workaround known.
- Until patched: keep Protected View enabled, block or restrict email attachments from untrusted senders, and treat unexpected Word documents with caution.
Exploitation
- Not known to be exploited; KEV: No.
- CISA SSVC: exploitation none, not automatable, total technical impact.
- No public proof of concept found.
Our recommendation
- Install the November 2026 Office update on all Word installations (Windows and Mac, Microsoft 365 and LTSC) and record the build numbers.
- Confirm the fixed builds on the Microsoft Security Update Guide, as they could not be verified here.
- Re-check the exploitation status (CISA KEV, vendor updates) in the coming days.
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 Update Guide: CVE-2026-111304 msrc.microsoft.com
- CVE Record: CVE-2026-111304 www.cve.org
- Strix: CVE-2026-111304 (secondary source, versions to be verified) www.strix.ai
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 10 Nov 2026, 23:06.
Original description (NVD)
Use after free in Microsoft Office Word allows an unauthorized attacker to execute code 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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