Home / Vulnerabilities / CVE-2021-34523
CRITICAL SEVERITY Ransomware Linked
CVE-2021-34523 Microsoft · Exchange Server

Microsoft Exchange Server Privilege Escalation Vulnerability

Critical Threat Advisory: This vulnerability is documented in active Ransomware campaigns. Immediate remediation required.

Technical Severity

CVSS v3.1 Metrics

CRITICAL
9 / 10
Minimal Risk Critical
Vector Specification
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N/E:U/RL:O/RC:C
Exploitation Likelihood

EPSS Prediction

94.00 %
Predictive Probability
Percentile Rank
99.9 th

Documented as more likely to be exploited than 99.9% of known CVEs.

Detection Date

Nov 03, 2021

Remediation Due

Nov 17, 2021

CISA Catalog Active

Threat Analysis

Microsoft Exchange Server contains an unspecified vulnerability that allows for privilege escalation.

Remediation Directive

Apply updates per vendor instructions.

External Intelligence