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Actively exploited

Listed in CISA’s Known Exploited Vulnerabilities catalog since November 3, 2021.

Known ransomware use

CVE-2021-31207

Microsoft Exchange Server Security Feature Bypass Vulnerability

Microsoft · Exchange Server

Added to KEV November 3, 2021

Alert details

Source feed
CISA KEV
CVE ID
CVE-2021-31207
CWE
CWE-20CWE-434
Affected products
Exchange Server · Microsoft Exchange Server · Microsoft

What happened

Microsoft Exchange Server contains an unspecified vulnerability that allows for security feature bypass.

What it means for your business

Microsoft Exchange Server is listed in CISA's Known Exploited Vulnerabilities catalog (CVE-2021-31207). Microsoft Exchange Server contains an unspecified vulnerability that allows for security feature bypass. 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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