Actively exploited
Listed in CISA’s Known Exploited Vulnerabilities catalog since November 17, 2021.
CVE-2021-42321
Microsoft Exchange Server Remote Code Execution Vulnerability
Added to KEV November 17, 2021
Alert details
- Source feed
- CISA KEV
- CVE ID
- CVE-2021-42321
- CWE
- CWE-184CWE-502
- Affected products
- Exchange · Microsoft Exchange · Microsoft
What happened
An authenticated attacker could leverage improper validation in cmdlet arguments within Microsoft Exchange and perform remote code execution.
What it means for your business
Microsoft Exchange is listed in CISA's Known Exploited Vulnerabilities catalog (CVE-2021-42321). An authenticated attacker could leverage improper validation in cmdlet arguments within Microsoft Exchange and perform remote code execution. CISA remediation due date: 2021-12-01. If you need help checking exposure, call (864) 335-9223.
Required action
Apply updates per vendor instructions.
CISA due date: December 1, 2021
Sources
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