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Vulnerability record · CVE-2026-55033 · published 14 July 2026

CVE-2026-55033: Microsoft 365 apps heap-based buffer overflow vulnerability

Microsoft · 365 Apps

Integer overflow or wraparound 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 overflowCWE-190 · Integer overflow
7.8CVSS 3.1 base score
0.57%EPSS exploitation probability, 30 days
NoNot in CISA KEV
7Affected product versions listed by NVD
1References
16 Jul 2026Last modified by NVD

Description

Integer overflow or wraparound 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

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

References

LinkTags
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55033 PatchVendor 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-2026-55033), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.