CVE-2021-26858 affects Microsoft Exchange Server. Review the CVSS score, exploitation signals, affected versions, remediation status, and linked source material before making a change.
CISA has listed this vulnerability in the Known Exploited Vulnerabilities catalog.
CVE-2021-26858 affects Microsoft Exchange Server. Review the CVSS score, exploitation signals, affected versions, remediation status, and linked source material before making a change.
Confirm exposure before applying a vendor-supported change.
Apply updates per vendor instructions.
Due date: 2022.05.03Confirm that Microsoft Exchange Server and an affected version are present.
Combine exploitation signals with asset exposure and business criticality.
Follow the vendor advisory or supported update path and preserve rollback options.
Recheck the version, service health, access paths, and relevant logs.
