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Vulnerability record · CVE-2026-56165 · published 24 July 2026

CVE-2026-56165: Microsoft account heap-based buffer overflow vulnerability

Microsoft · Account

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

9.8 CVSS 3.1 Critical EPSS 0.97% · top 39.4% CWE-122 · Heap-based buffer overflow
9.8CVSS 3.1 base score
0.97%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
1References
30 Jul 2026Last modified by NVD

Description

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

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

Affected products

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

References

LinkTags
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56165 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-2026-56165), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.