CVE-2026-20955

HIGH

Microsoft Office Excel - Code Injection

Title source: llm
STIX 2.1

Description

Untrusted pointer dereference in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

Scores

CVSS v3 7.8
EPSS 0.0007
EPSS Percentile 21.7%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact total

Details

CWE
CWE-822
Status published
Products (12)
microsoft/365_apps (2 CPE variants)
Microsoft/Microsoft 365 Apps for Enterprise 16.0.1 - https://aka.ms/OfficeSecurityReleases
Microsoft/Microsoft Office 2019 19.0.0 - https://aka.ms/OfficeSecurityReleases
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 - 16.105.26011018
Microsoft/Microsoft Office LTSC for Mac 2024 16.0.0 - 16.105.26011018
microsoft/office 2019 (2 CPE variants)
Microsoft/Office Online Server 16.0.0.0 - 16.0.10417.20083
microsoft/office_long_term_servicing_channel 2021 (3 CPE variants)
... and 2 more
Published Jan 13, 2026
Tracked Since Feb 18, 2026