{"cvss":8.8,"datePublished":"2026-04-13","dateUpdated":"2026-04-13","description":"Microsoft Exchange Server contains a deserialization of untrusted data that allows an authenticated attacker to achieve remote code execution.","dueDate":"2026-04-27","id":"CVE-2023-21529","kev_catalogs":["cisa"],"knownRansomwareCampaignUse":"Known","notes":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21529 ; https://nvd.nist.gov/vuln/detail/CVE-2023-21529","product":"Exchange Server","requiredAction":"Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.","severity":"HIGH","source":"cisa_known_exploited","title":"Microsoft Exchange Server Deserialization of Untrusted Data Vulnerability","vendor":"Microsoft"}