#VU109089 Type Confusion in Microsoft products - CVE-2025-30383

Vulnerability identifier: #VU109089

Vulnerability risk: High

CVSSv4.0: 5.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2025-30383

CWE-ID: CWE-843

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Office Online Server
Server applications / Other server solutions
Microsoft Office
Client/Desktop applications / Office applications
Microsoft Excel
Client/Desktop applications / Office applications
Microsoft 365 Apps for Enterprise
Client/Desktop applications / Office applications
Microsoft Office LTSC
Client/Desktop applications / Other client software

Vendor: Microsoft

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a type confusion error in Microsoft Excel. A remote attacker can pass specially crafted data to the application, trigger a type confusion error and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Office Online Server : All versions

Microsoft Office: 2019

Microsoft Excel: 2016

Microsoft Office LTSC: 2021 - 2024

Microsoft 365 Apps for Enterprise: 32-bit Systems, 64-bit Systems

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External links
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-30383

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.