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CVE

CVE-2023-21529

P1⬤ KNOWN RANSOMWARE USE

Microsoft Exchange Server Deserialization of Untrusted Data Vulnerability

Microsoft · Exchange Server

Date added (CISA)

2026-04-13

Remediation due

2026-04-27

Known ransomware use

Yes

Remediation priority

P1 — known ransomware use · past CISA due date

Related

Nothing linked yet

No threat actor or pipeline report has been cross-referenced against this CVE yet.

Source: NVD ↗ · CISA KEV Catalog ↗