Microsoft Exchange Server Remote Code Execution Vulnerability
CVE-2021-26857

7.8HIGH

Key Information:

Vendor
Microsoft
Status
Microsoft Exchange Server 2016 Cumulative Update 19
Microsoft Exchange Server 2019 Cumulative Update 8
Microsoft Exchange Server 2019
Microsoft Exchange Server 2013 Cumulative Update 22
Vendor
CVE Published:
3 March 2021

Badges

💰 Ransomware👾 Exploit Exists🟡 Public PoC🟣 EPSS 61%🦅 CISA Reported

Summary

Microsoft Exchange Server Remote Code Execution Vulnerability

CISA Reported

CISA provides regional cyber and physical services to support security and resilience across the United States. CISA monitor the most dangerious vulnerabilities and have identifed as being exploited and is known by the CISA as enabling ransomware campaigns.

The CISA's recommendation is: Apply updates per vendor instructions.

Affected Version(s)

Microsoft Exchange Server 2010 Service Pack 3 Unknown 14.0.0.0

Microsoft Exchange Server 2013 Cumulative Update 21 x64-based Systems 15.00.0

Microsoft Exchange Server 2013 Cumulative Update 22 x64-based Systems 15.00.0

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

Proxylogon-exploit
Created by sirpedrotavares

References

https://portal.msrc.microsoft.com/en-US/security-guidance...
x_refsource_MISC

EPSS Score

61% chance of being exploited in the next 30 days.

CVSS V3.1

Score:
7.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Local
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • 💰

    Used in Ransomware

  • 🦅

    CISA Reported

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Collectors

NVD DatabaseMitre DatabaseCISA Database1 Proof of Concept(s)
.