Microsoft Office Outlook: Remote code execution via use after free
Summary
A use-after-free weakness (CWE-416) in Microsoft Office Outlook allows an unauthorized attacker to execute code over the network. According to secondary reports, the attacker would need to send a specially crafted message file and trick the recipient into opening it, so user interaction is required. Exploitation is not indicated for this CVE, and the impact is rated total (CVSS 3.1 base score 8.8).
Affected
- Microsoft 365 Apps for Enterprise (from 16.0.1, before the fixed build on the Office security release page)
- Office 365 for Mac (from 1.0.0 before 16.115.26110837)
- Office LTSC 2021 (from 16.0.1 before 16.0.14334.21048)
- Office LTSC 2024 (listed as affected from 16.0.0; fixed build not confirmed in the CVE record)
- Office LTSC for Mac 2021 and 2024 (from 16.0.0 or 16.0.1 before 16.115.26110837 per CNA record, to be verified)
Fixed in
- Microsoft 365 Apps for Enterprise: Unknown, verify on MSRC and aka.ms/OfficeSecurityReleases
- Office 365 for Mac: 16.115.26110837
- Office LTSC 2021: 16.0.14334.21048
- Office LTSC 2024: Unknown, third-party source indicates 16.0.17932.21140, verify with the vendor
- Office LTSC for Mac 2021 and 2024: Unknown, third-party source indicates 16.115.26110837, verify with the vendor
Workaround
Unknown. No vendor-documented workaround was found. Interim measures that are not from sources: restrict or sandbox risky attachment types at the mail gateway and train users not to open unexpected message or Office files.
Exploitation
- Exploited in the wild: not indicated for this CVE.
- Public proof of concept: unknown.
- CISA SSVC: Exploitation none, Automatable no, Technical Impact total.
Our recommendation
- Patch Microsoft 365 Apps and Office LTSC clients with priority.
- Verify the fixed build numbers on the MSRC advisory and aka.ms/OfficeSecurityReleases before rollout.
- Confirm that all endpoints run the fixed builds, including Mac clients.
- Filter risky attachments at the mail gateway and train users to be careful with unexpected files.
- Monitor for updates to the NVD analysis, which was pending at publication.
Information from Microsoft (Patch Tuesday November 2026)
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- MSRC Security Update Guide msrc.microsoft.com
- CVE.org CVE Record www.cve.org
- Cybersecurity News: November 2026 Patch Tuesday cybersecuritynews.com
- Rescana: Patch Tuesday November 2026 www.rescana.com
- Strix AI: CVE-2026-110068 www.strix.ai
- Trinetriops: Patch Tuesday November 2026 trinetriops.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 10 Nov 2026, 23:18.
Original description (NVD)
Use after free in Microsoft Office Outlook 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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