CVE-2023-21529: Microsoft Exchange Server Deserialization of Untrusted Data Vulnerability

Published Feb 14, 2023
·
Updated

Microsoft Exchange Server contains a deserialization of untrusted data that allows an authenticated attacker to achieve remote code execution.

Other sources

Microsoft Exchange Server Remote Code Execution Vulnerability

Microsoft

Affected Software

9 affected componentsFixes available
Microsoft Exchange Server=2013-cumulative_update_23
Microsoft Exchange Server=2016-cumulative_update_23
Microsoft Exchange Server=2019-cumulative_update_11
Microsoft Exchange Server=2019-cumulative_update_12
Microsoft Exchange Server
Microsoft Exchange Server 2016=23
15.01.2507.021
Microsoft Exchange Server 2019=12
15.02.1118.025
Microsoft Exchange Server 2019=11
15.02.0986.041
Microsoft Exchange Server 2013=23
15.00.1497.047

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 15.01.2507.021Patch KB5023038
  2. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 15.02.1118.025Patch KB5023038
  3. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 15.02.0986.041Patch KB5023038
  4. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 15.00.1497.047Patch KB5023038

Event History

Feb 14, 2023
CVE Published
via Microsoft·08:00 AM
Data Sourced
via Microsoft·08:00 AM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·08:00 AM
Affected Software
Updated
via Microsoft·08:00 AM
Description
CVE Published
via MITRE·07:33 PM
Data Sourced
via MITRE·07:33 PM
DescriptionSeverity
Data Sourced
via NVD·08:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
Apr 6, 2026
News Published
via BleepingComputer·04:56 PM
News Published
via BleepingComputer·04:57 PM
Apr 13, 2026
Known Exploited
via CISA·12:00 AM
Known Ransomware
via CISA·12:00 AM
Data Sourced
via CISA·12:00 AM
RemedyDescriptionAffected Software
News Published
via The Register·09:35 PM
News Published
via The Register·09:37 PM
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Frequently Asked Questions

1

What is CVE-2023-21529?

CVE-2023-21529 is a vulnerability in Microsoft Exchange Server that allows remote code execution.

2

How severe is CVE-2023-21529?

CVE-2023-21529 has a severity level of 8.8, which is considered high.

3

Which versions of Microsoft Exchange Server are affected by CVE-2023-21529?

CVE-2023-21529 affects Microsoft Exchange Server 2013, 2016, and 2019 with specific cumulative updates.

4

How can I fix CVE-2023-21529?

To fix CVE-2023-21529, you need to apply the relevant cumulative update or patch provided by Microsoft.

5

Where can I find more information about CVE-2023-21529?

You can find more information about CVE-2023-21529 on the Microsoft Security Response Center's website.

Contact

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