CVE-2026-77902: microsoft 365_apps, microsoft microsoft_365, microsoft office_2021

CVSS 8.8 (high) · published 2026-10-13

Heap-based buffer overflow in Microsoft Office Excel 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-122

Source: NVD CVE-2026-77902

References

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-77902

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