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Vulnerability record · CVE-2026-55127 · published 14 July 2026

CVE-2026-55127: Microsoft 365 apps heap-based buffer overflow vulnerability

Microsoft · 365 Apps

Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code locally.

7.8 CVSS 3.1 High EPSS 0.57% · top 55.0% CWE-122 · Heap-based buffer overflow
7.8CVSS 3.1 base score
0.57%EPSS exploitation probability, 30 days
NoNot in CISA KEV
8Affected product versions listed by NVD
1References
16 Jul 2026Last modified by NVD

Description

Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code locally.

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

Affected products

8 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55127 Vendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-55127), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.