CVE-2025-21402 Microsoft Office OneNote Remote Code Execution Vulnerability

What is CVE-2025-21402?

CVE-2025-21402 is a high-severity code injection vulnerability in Microsoft Office, published on 14 Jan 2025. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

Official description

Microsoft Office OneNote Remote Code Execution Vulnerability

Weakness: CWE-641

Which versions are affected by CVE-2025-21402?

It affects 3 products.

Products include Microsoft Office, Microsoft Office Long Term Servicing Channel, Microsoft Onenote.

How do I fix CVE-2025-21402?

No fix has been published for CVE-2025-21402 yet. Limit exposure of the affected software until one is available.

Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.

Is CVE-2025-21402 being exploited?

There is no known exploitation of CVE-2025-21402 in the wild and no public exploit code.

Other vulnerabilities in Microsoft Office

• CVE-2018-0798 Microsoft Office Memory Corruption Exploited High 8.8
• CVE-2015-1770 Microsoft Office Uninitialized Memory Use Exploited High 8.8
• CVE-2006-2492 Microsoft Word Malformed Object Pointer Exploited High 8.8
• CVE-2018-0802 Microsoft Office Memory Corruption Exploited High 7.8
• CVE-2017-11882 Microsoft Office Memory Corruption Exploited High 7.8

All Microsoft Office vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-hf5r-fmgp-v332.