CVE-2023-36745Public exploit

Authenticated code execution via PowerShell remoting deserialization

Published Sep 12, 2023 · Updated Oct 30, 2025

Deserialization in Microsoft Exchange Server 2016 CU23 and 2019 CU12-CU13 allows remote authenticated users to execute arbitrary code. PowerShell remoting type resolution accepts attacker-controlled serialized type data and loads a referenced .NET assembly from an SMB share. A domain account and adjacent-network access to Exchange PowerShell remoting are required, and successful exploitation runs commands on the server.

CVSS severity8.0
High
EPSS probability79.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Deserialization in Microsoft Exchange Server 2016 CU23 and 2019 CU12-CU13 allows remote authenticated users to execute arbitrary code. PowerShell remoting type resolution accepts attacker-controlled serialized type data and loads a referenced .NET assembly from an SMB share. A domain account and adjacent-network access to Exchange PowerShell remoting are required, and successful exploitation runs commands on the server.

The record

CVE
CVE-2023-36745
Published
Sep 12, 2023
Updated
Oct 30, 2025
Vendor
Microsoft
Product
Microsoft Exchange Server 2019 Cumulative Update 12
Classifications
CWE-502, T1059.001, T1210
Attack vector
adjacent
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 12, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 30, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=15.02.0 <15.02.1118.037

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesauthenticated

What is affected?

Microsoft · Microsoft Exchange Server 2019 Cumulative Update 12version=15.02.0 <15.02.1118.037
Microsoft · Microsoft Exchange Server 2019 Cumulative Update 13version=15.02.0 <15.02.1258.025
Microsoft · Microsoft Exchange Server 2016 Cumulative Update 23version=15.01.0 <15.01.2507.032

Published CVSS scores

8.0Microsoft CorporationCVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data
T1059.001PowerShell
T1210Exploitation of Remote Services

Public exploit references

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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