CVE-2026-69629 Heap-based buffer overflow in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network

Description

Heap-based buffer overflow in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network.

Affected products and versions

Product	Affected versions	Fixed in
Microsoft 365 Apps for Enterprise 16.0	16.0.1 → < 16.0.20326.20138	16.0.20326.20138
Microsoft Office 2019 16.0	earliest → < 16.0.10417.20207	16.0.10417.20207
Microsoft Office LTSC 2021 16.0	16.0.1 → < 16.0.14334.20906	16.0.14334.20906
Microsoft Office LTSC 2024 16.0	16.0.0 → < 16.0.17932.20976	16.0.17932.20976
Microsoft Outlook 2016 16.0	16.0.0.0 → < 16.0.5569.1002	16.0.5569.1002

Other CVEs of Microsoft 365 Apps for Enterprise

The 931 CVEs of Microsoft 365 Apps for Enterprise →

CVE-2026-108454 Buffer over-read in Microsoft Office PowerPoint allows an unauthorized attacker to disclose information over a network 6.5 Medium CVE-2026-108455 Out-of-bounds read in Microsoft Office PowerPoint allows an unauthorized attacker to disclose information over a network 6.5 Medium CVE-2026-108453 Out-of-bounds read in Microsoft Office PowerPoint allows an unauthorized attacker to disclose information over a network 6.5 Medium CVE-2026-108451 Numeric truncation error in Microsoft Office Word allows an unauthorized attacker to execute code over a network 8.8 High