CVE-2026-45583: Microsoft Exchange Server Remote Code Execution Vulnerability
Improper control of generation of code ('code injection') in Microsoft Exchange Server allows an unauthorized attacker to execute code over a network.
Other sources
Microsoft Exchange Server Remote Code Execution Vulnerability
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 15.02.1544.043Patch KB5103214 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 15.02.2562.045Patch KB5103212 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 15.02.1748.048Patch KB5103213 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 15.01.2507.071Patch KB5103215
Event History
Frequently Asked Questions
What is the severity of CVE-2026-45583?
CVE-2026-45583 has a severity score of 8.1, categorized as high.
What software is affected by CVE-2026-45583?
CVE-2026-45583 affects Microsoft Exchange Server 2019, Microsoft Exchange Server 2016, and the Microsoft Exchange Server Subscription Edition.
How do I fix CVE-2026-45583?
To fix CVE-2026-45583, apply the latest security updates provided by Microsoft for affected versions of Exchange Server.
What type of vulnerability is CVE-2026-45583?
CVE-2026-45583 is classified as a Remote Code Execution vulnerability due to improper control of code generation.
What are the potential impacts of CVE-2026-45583?
Exploitation of CVE-2026-45583 could allow an unauthorized attacker to execute arbitrary code on the affected Microsoft Exchange Server.