CVE-2023-36745
HighExploitedMicrosoft Exchange Server Remote Code Execution Vulnerability
Published Sep 13, 2023 · Updated Oct 30, 2025
Key Facts
Patch immediately- CVE-2023-36745 is a high-severity vulnerability (CVSS 8.0 v3.1) affecting Exchange Server (Microsoft), Microsoft Exchange Server 2016 Cumulative Update 23, Microsoft Exchange Server 2019 Cumulative Update 12 and 1 more product.
- It is exploited in the wild, listed in Industry KEV feed since May 24, 2024. No public exploit code is known.
- EPSS estimates a 80% probability of exploitation in the next 30 days.
- Fixed versions are available, including Microsoft Exchange Server 2016 Cumulative Update 23 15.01.2507.032, Microsoft Exchange Server 2019 Cumulative Update 12 15.02.1118.037, Microsoft Exchange Server 2019 Cumulative Update 13 15.02.1258.025.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
8.0
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
80%
Higher than 99.6% of all scored CVEs
Exploited in the wild
Yes
1 catalog listing
Public exploit code
None known
Get the full CVE-2023-36745 brief as a PDF
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Description
Microsoft Exchange Server Remote Code Execution Vulnerability
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| Industry KEV feed | May 24, 2024 | n/a | Not reported |
Required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Affected Products
6 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Exchange ServerMicrosoft | 2016-cumulative_update_23, 2019-cumulative_update_12, 2019-cumulative_update_13 | n/a |
| Microsoft Exchange Server 2016 Cumulative Update 23 | >= 15.01.0 | 15.01.2507.032 |
| Microsoft Exchange Server 2019 Cumulative Update 12 | >= 15.02.0 | 15.02.1118.037 |
| Microsoft Exchange Server 2019 Cumulative Update 13 | >= 15.02.0 | 15.02.1258.025 |
Patched Releases
Microsoft Exchange Server 2016 Cumulative Update 23
15.01.2507.032
Microsoft Exchange Server 2019 Cumulative Update 12
15.02.1118.037
Microsoft Exchange Server 2019 Cumulative Update 13
15.02.1258.025
Timeline
Publicly disclosed
Sep 13, 2023
Added to Industry KEV feed
May 24, 2024
Last updated
Oct 30, 2025
Weakness Type
- CWE-502 Deserialization of Untrusted Data
References
- advisoryhttps://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2023-36744
- advisoryhttps://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2023-36745
- advisoryhttps://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2023-36756
- advisoryhttps://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2023-36757
- advisoryhttps://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2023-36777
FAQ
Common Questions.
Microsoft Exchange Server Remote Code Execution Vulnerability
Affected: Exchange Server (Microsoft) versions 2016-cumulative_update_23, 2019-cumulative_update_12, 2019-cumulative_update_13; Microsoft Exchange Server 2016 Cumulative Update 23 versions >= 15.01.0; Microsoft Exchange Server 2019 Cumulative Update 12 versions >= 15.02.0, among others. The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed since May 24, 2024.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including Microsoft Exchange Server 2016 Cumulative Update 23 15.01.2507.032, Microsoft Exchange Server 2019 Cumulative Update 12 15.02.1118.037, Microsoft Exchange Server 2019 Cumulative Update 13 15.02.1258.025.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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