CVE-2026-88156: microsoft 365_apps, microsoft microsoft_365, microsoft office_2021

CVSS 9.8 (critical) · published 2026-10-13

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

Affected products (NVD): microsoft 365_apps, microsoft microsoft_365, microsoft office_2021, microsoft office_2024

Weakness: CWE-121

Source: NVD CVE-2026-88156

References

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-88156

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