CVE-2026-55007

HighCVSS 8.1/10Last modified Oct 5, 2026

Description

Double free in Microsoft Exchange Server allows an unauthorized attacker to execute code over a network.

Metrics

CVSS 3.1 8.1/10CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness enumeration

CWE-415

Affected software

Vendor	Product	Versions
Microsoft	Microsoft Exchange Server 2019 Cumulative Update 14	>= 15.02.0.0, < 15.02.1544.046
Microsoft	Microsoft Exchange Server 2019 Cumulative Update 15	>= 15.02.0.0, < 15.02.1748.051
Microsoft	Microsoft Exchange Server Subscription Edition RTM	>= 15.02.0.0, < 15.02.2562.049

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55007Patch, Vendor Advisory

Timeline

Published: Sep 8, 2026
Last modified: Oct 5, 2026
NVD status: Analyzed

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