CRITICAL🚩 CISA KEV⚡ EXPLOIT✓ PATCH🇵🇱 Wersja polska

CVE-2021-34523

CVSS 9.0v3.1pub. 2021-07-14upd. 2026-08-10

Microsoft Exchange Server Elevation of Privilege Vulnerability

CVSS Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N

  • Microsoft Exchange Server

    APP
    Microsoft
    201320162019

CISA KEV — detailsi

Vendori
Microsoft ↗
Producti
Exchange Server
Added to KEVi
November 3, 2021
Remediation deadline (US Federal)i
November 17, 2021(overdue)
Ransomwarei
Active ransomware campaigns exploit this vulnerability
Required action (CISA)i

Apply updates per vendor instructions.

CISA descriptioni

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

🔴
IMMEDIATE ACTION
Actively exploited in the wild (CISA KEV). Patch immediately.
☠️WYKORZYSTYWANE W RANSOMWARE⏰CISA DEADLINE: 17 listopada 2021
CWE
References

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