CVE-2026-55138

MediumCVSS 5.5/10Last modified Jul 15, 2026

Description

Untrusted pointer dereference in Microsoft Office Excel allows an unauthorized attacker to disclose information locally.

Metrics

CVSS 3.1 5.5/10CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

Weakness enumeration

CWE-822

Affected software

Vendor	Product	Versions
Microsoft	Microsoft 365 Apps for Enterprise	>= 16.0.1, < https://aka.ms/OfficeSecurityReleases
Microsoft	Microsoft Excel 2016	>= 16.0.0.0, < 16.0.5561.1001
Microsoft	Microsoft Office 2019	>= 19.0.0, < https://aka.ms/OfficeSecurityReleases
Microsoft	Microsoft Office 365 for Mac	>= 1.0.0, < 16.111.26071215
Microsoft	Microsoft Office LTSC 2021	>= 16.0.1, < https://aka.ms/OfficeSecurityReleases
Microsoft	Microsoft Office LTSC 2024	>= 16.0.0, < https://aka.ms/OfficeSecurityReleases
Microsoft	Microsoft Office LTSC for Mac 2021	>= 16.0.1, < 16.111.26071215
Microsoft	Microsoft Office LTSC for Mac 2024	>= 16.0.0, < 16.111.26071215
Microsoft	Office Online Server	>= 16.0.0.0, < 16.0.10417.20175

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55138Vendor Advisory

Timeline

Published: Jul 14, 2026
Last modified: Jul 15, 2026
NVD status: Analyzed

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