Microsoft PowerPoint: Heap-based buffer overflow enabling code execution
Summary
Microsoft PowerPoint in Microsoft 365 Apps for Enterprise and Office LTSC 2021 and 2024 contains a heap-based buffer overflow (CWE-122). A remote attacker without authentication can execute code over the network, which in practice could give full control over the affected user's session and workstation. The attack requires the user to take an action, such as opening a crafted presentation, but no privileges are needed. The CVSS base score is 8.8 (High).
Affected
- Microsoft 365 Apps for Enterprise: 16.0.1 up to the fixed build (build number unknown)
- Microsoft Office LTSC 2021: 16.0.1 before 16.0.14334.20974
- Microsoft Office LTSC 2024: 16.0.0 before 16.0.17932.21056
Fixed in
- Office LTSC 2021: 16.0.14334.20974
- Office LTSC 2024: 16.0.17932.21056
- Microsoft 365 Apps for Enterprise: Unknown. The CNA record only links to https://aka.ms/OfficeSecurityReleases.
Workaround
Unknown. No vendor workaround found; the patch is the primary remedy.
- Until patched, limit exposure to untrusted Office files, such as email attachments from unknown senders (general recommendation, not stated by a source).
Exploitation
- Exploited in the wild: no evidence found.
- CISA SSVC: exploitation none, automatable no, technical impact total.
- Public proof of concept: none found.
- KEV status: not confirmed (one aggregator lists No).
Our recommendation
- Patch Microsoft 365 Apps and Office LTSC 2021/2024 to the fixed builds as a priority in the next maintenance window; verify the Microsoft 365 Apps build against the MSRC advisory.
- Until patched, block or quarantine Office attachments from unknown senders and make users aware of unexpected documents.
- Monitor for exploitation and check the MSRC advisory and CISA KEV for updates.
Information from Microsoft (Patch Tuesday November 2026)
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- CVE.org CNA record CVE-2026-120005 www.cve.org
- Microsoft Security Update Guide CVE-2026-120005 msrc.microsoft.com
- Cybersecuritynews: Microsoft November 2026 Patch Tuesday cybersecuritynews.com
- Strix: CVE-2026-120005 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, 21:33.
Original description (NVD)
Heap-based buffer overflow in Microsoft Office PowerPoint 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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