Authenticated code execution via unsafe deserialization
Published Feb 14, 2023 · Updated Aug 19, 2026
Deserialization in Microsoft Exchange Server 2016 CU23 and 2019 CU11 through CU12 allows remote authenticated users to execute code over the network. Microsoft has not published the affected component, serialized input, or deserialization operation that accepts it. Exploitation requires administrative privileges, and successful exploitation executes attacker-controlled code on the Exchange server.
Summary
What happened
Deserialization in Microsoft Exchange Server 2016 CU23 and 2019 CU11 through CU12 allows remote authenticated users to execute code over the network. Microsoft has not published the affected component, serialized input, or deserialization operation that accepts it. Exploitation requires administrative privileges, and successful exploitation executes attacker-controlled code on the Exchange server.
The record
- CVE
- CVE-2023-21710
- Published
- Feb 14, 2023
- Updated
- Aug 19, 2026
- Vendor
- Microsoft
- Product
- Microsoft Exchange Server 2019 Cumulative Update 12
- Classifications
- CWE-502, T1190
- Attack vector
- network
- Privileges
- admin
Timeline
How it unfolded
- Feb 14, 2023CVE publishedPublication date reported by the CVE source.
- Aug 19, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=15.02.0 <15.02.1118.025
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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