CVE-2026-55005 - Vulnerability Details - OpenCVE

Heap-based buffer overflow in Microsoft Exchange Server allows an authorized attacker to execute code over a network.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00663.

Exploitation none

Automatable no

Technical Impact total

Vendors	Products
Microsoft	Exchange Server 2016 Exchange Server 2019 Exchange Server Se

No data.

No data.

OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.

Vendors	Products
Microsoft	Exchange Server 2016 Exchange Server 2019 Exchange Server Se

References

Link	Providers
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55005

History

Wed, 15 Jul 2026 12:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Tue, 14 Jul 2026 17:15:00 +0000

Type	Values Removed	Values Added
Description		Heap-based buffer overflow in Microsoft Exchange Server allows an authorized attacker to execute code over a network.
Title		Microsoft Exchange Server Remote Code Execution Vulnerability
First Time appeared		Microsoft Microsoft exchange Server 2016 Microsoft exchange Server 2019 Microsoft exchange Server Se
Weaknesses		CWE-122
CPEs		cpe:2.3:a:microsoft:exchange_server_2016::cumulative_update_23::::::* cpe:2.3:a:microsoft:exchange_server_2019::cumulative_update_14::::::* cpe:2.3:a:microsoft:exchange_server_2019::cumulative_update_15::::::* cpe:2.3:a:microsoft:exchange_server_se::RTM::::::*
Vendors & Products		Microsoft Microsoft exchange Server 2016 Microsoft exchange Server 2019 Microsoft exchange Server Se
References		https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55005
Metrics		cvssV3_1 `{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C'}`

MITRE

Status: PUBLISHED

Assigner: microsoft

Published: 2026-07-14T17:04:57.884Z

Updated: 2026-07-15T22:22:48.462Z

Reserved: 2026-06-16T14:10:05.869Z

Link: CVE-2026-55005

Vulnrichment

Updated: 2026-07-15T10:59:12.695Z

NVD

No data.

Redhat

No data.

OpenCVE Enrichment

Updated: 2026-07-15T10:30:05Z

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