Actively exploited
Listed in CISA’s Known Exploited Vulnerabilities catalog since November 3, 2021.
CVE-2021-34523
Microsoft Exchange Server Privilege Escalation Vulnerability
Added to KEV November 3, 2021
Alert details
- Source feed
- CISA KEV
- CVE ID
- CVE-2021-34523
- CWE
- CWE-287
- Affected products
- Exchange Server · Microsoft Exchange Server · Microsoft
What happened
Microsoft Exchange Server contains an unspecified vulnerability that allows for privilege escalation.
What it means for your business
Microsoft Exchange Server is listed in CISA's Known Exploited Vulnerabilities catalog (CVE-2021-34523). Microsoft Exchange Server contains an unspecified vulnerability that allows for privilege escalation. CISA remediation due date: 2021-11-17. If you need help checking exposure, call (864) 335-9223.
Required action
Apply updates per vendor instructions.
CISA due date: November 17, 2021
Sources
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