Microsoft Office: Use-after-free leading to remote code execution
Summary
A use-after-free vulnerability in Microsoft Office allows an unauthenticated attacker to execute code over the network. Exploitation requires a victim to interact, for example by opening a crafted document, and the CVSS attack complexity is high. A successful attack would run code in the context of the logged-on user, with high impact on confidentiality, integrity and availability.
Affected
- Microsoft 365 Apps for Enterprise: 16.0.1 up to the fixed build (build number not stated in the CVE record; see the MSRC advisory)
- Microsoft Office 365 for Mac: before 16.115.26110837
- Microsoft Office LTSC 2021: before 16.0.14334.21048
- Microsoft Office LTSC 2024: before 16.0.17932.21140
- Microsoft Office LTSC for Mac 2021: before 16.115.26110837
- Microsoft Office LTSC for Mac 2024: before 16.115.26110837
Fixed in
- Microsoft Office 365 for Mac: 16.115.26110837
- Microsoft Office LTSC 2021: 16.0.14334.21048
- Microsoft Office LTSC 2024: 16.0.17932.21140
- Microsoft 365 Apps for Enterprise: Unknown. Check the MSRC advisory.
- Mac LTSC 2021 and 2024 builds: listed in the CNA record, to be verified against the MSRC advisory
Workaround
Unknown. No workaround or mitigation was found in the available sources. Check the FAQ section of the MSRC advisory.
Exploitation
- No evidence of active exploitation found at publication.
- No public proof of concept found.
- CISA SSVC assessment: Exploitation none, Automatable no, Technical Impact total.
- Not confirmed against the live CISA KEV catalog.
Our recommendation
- Identify all Office clients and their installed builds and update channels.
- Install the November 2026 Office security updates as part of the normal update cycle.
- Confirm that Protected View and attachment filtering are enabled for email and downloaded documents.
- Re-check the MSRC advisory and the CISA KEV catalog in one to two weeks, and accelerate patching if exploitation is reported.
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: CVE-2026-111286 msrc.microsoft.com
- CVE.org record CVE-2026-111286 www.cve.org
- Strix.ai: CVE-2026-111286 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 11 Nov 2026, 05:58.
Original description (NVD)
Use after free in Microsoft Office 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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