CVE-2023-21529 — Microsoft Exchange Server Deserialization of Untrusted Data Vulnerability
CVE-2023-21529: Microsoft Exchange Server Deserialization of Untrusted Data Vulnerability
CISA Known Exploited Vulnerability (KEV)
| Vendor / project | Microsoft |
| Product | Exchange Server |
| Date added | 2026-04-13 |
| Due date | 2026-04-27 |
| Ransomware campaign use | Known |
Description
Microsoft Exchange Server contains a deserialization of untrusted data that allows an authenticated attacker to achieve remote code execution.
Required action (CISA)
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Notes
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21529 ; https://nvd.nist.gov/vuln/detail/CVE-2023-21529
References
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-21529
- KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog