Microsoft Office: Information disclosure through out-of-bounds read
Summary
Microsoft Office contains an out-of-bounds read (CWE-125). An unauthenticated remote attacker can use it to read small portions of heap memory and disclose information, but only if a user is tricked into performing an action. The impact is limited to confidentiality; the vendor does not describe code execution. CVSS 3.1 base score is 6.5 (Medium), and Microsoft rates it Important.
Affected
- Microsoft 365 Apps for Enterprise (32- and 64-bit): 16.0.1 up to the build listed in the Microsoft advisory
- Office LTSC 2021: before 16.0.14334.21048
- Office LTSC 2024: 16.0.0 before 16.0.17932.21140
- Office 2019 and Office for Mac: unknown, check the advisory
Fixed in
- Office LTSC 2021: 16.0.14334.21048
- Office LTSC 2024: 16.0.17932.21140
- Microsoft 365 Apps for Enterprise: November 2026 security update for your update channel (exact build per the Microsoft advisory)
- Release date: November 10, 2026
Workaround
Unknown. No vendor-documented workaround. Apply the update.
Exploitation
- Exploited in the wild: no evidence for this CVE
- Public exploit: none known
- CISA KEV: not listed as far as known (catalogue not checked directly)
- CISA SSVC: exploitation none, automatable no, technical impact partial
Our recommendation
- Confirm the installed Office build on all endpoints, especially LTSC 2021 and LTSC 2024 installations, which may lag behind
- Install the November 2026 security update for each update channel
- Patch the Outlook zero-day CVE-2026-124194 first
- Until patched, be cautious with unsolicited Office documents from unknown senders
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-2026-111291 msrc.microsoft.com
- CVE Record CVE-2026-111291 www.cve.org
- Microsoft 365 Apps security updates learn.microsoft.com
- Rapid7: Microsoft Patch Tuesday November 2026 www.rapid7.com
- Cybersecurity News: Outlook zero-day vulnerability cybersecuritynews.com
- TBreak: Outlook zero-day, November 2026 Patch Tuesday tbreak.com
- Strix: CVE-2026-111291 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, 12:31.
Original description (NVD)
Out-of-bounds read in Microsoft Office 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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