Microsoft Exchange Server Security Feature Bypass Vulnerability
CVE-2021-31207

6.6MEDIUM

Key Information:

Vendor

Microsoft
Status
Microsoft Exchange Server 2013 Cumulative Update 23
Microsoft Exchange Server 2019 Cumulative Update 9
Microsoft Exchange Server 2016 Cumulative Update 20
Microsoft Exchange Server 2016 Cumulative Update 19
Vendor
CVE Published:
11 May 2021

Badges

💰 Ransomware👾 Exploit Exists🟣 EPSS 94%🦅 CISA Reported

What is CVE-2021-31207?

Microsoft Exchange Server Security Feature Bypass Vulnerability

CISA has reported CVE-2021-31207

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 CVE-2021-31207 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 2013 Cumulative Update 23 x64-based Systems 15.00.0 < 15.00.1497.018

Microsoft Exchange Server 2016 Cumulative Update 19 x64-based Systems 15.01.0 < 15.01.2176.014

Microsoft Exchange Server 2016 Cumulative Update 20 x64-based Systems 15.01.0 < 15.01.2242.010

References

https://portal.msrc.microsoft.com/en-US/security-guidance...
x_refsource_MISC
https://www.zerodayinitiative.com/advisories/ZDI-21-819/
x_refsource_MISC
http://packetstormsecurity.com/files/163895/Microsoft-Exc...
x_refsource_MISC

EPSS Score

94% chance of being exploited in the next 30 days.

CVSS V3.1

Score:
6.6
Severity:
MEDIUM
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
High
Privileges Required:
High
User Interaction:
None
Scope:
Unchanged

Timeline

  • 💰

    Used in Ransomware

  • 👾

    Exploit known to exist

  • 🦅

    CISA Reported

  • Vulnerability published

  • Vulnerability Reserved

.