All vulnerabilities
CVE-2020-0688

Microsoft Exchange Server Validation Key Remote Code Execution Vulnerability

Microsoft Exchange ServerApplications & CMS
Open in ThreatlineRecord JSON
CVSS
8.8High
ExploitationExploited in the wildAdded to KEV 3 Nov 2021. Known ransomware useCISA KEV
Exploit odds (EPSS)>99.9%Chance of exploitation activity in the next 30 days, higher than 99.9% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed inNone listedNo source names a fixed version. Check the vendor advisory below
Federal deadline3 May 2022Remediation due date for US federal agenciesCISA KEV
CISA required actionApply updates per vendor instructions. CISA KEV

What fixes it

No source in this snapshot names a fixed version. The vendor advisories under References are the place to check.

Timeline

  1. 11 Feb 2020Exploit code publicMetasploit
  2. 11 Feb 2020, 21:22 UTCPublishedCVE List
  3. 3 Nov 2021Added to CISA KEVCISA KEV

Public exploit code and templates 3

  • Exploit moduleExchange Control Panel ViewState Deserialization 11 Feb 2020Metasploit
  • Remote exploitExchange Control Panel - Viewstate Deserialization (Metasploit) 5 Mar 2020Exploit-DB
  • Remote exploitMicrosoft Exchange 2019 15.2.221.12 - Authenticated Remote Code Execution 2 Mar 2020Exploit-DB

Listed so defenders can prioritize. Threatline links to the source and does not host exploit code.

Description

Microsoft Exchange Server Validation Key fails to properly create unique keys at install time, allowing for remote code execution.

Text from CVE List

Affected versions 6

  • Microsoft Exchange Server 2013affected: Cumulative Update 23CVE List
  • Microsoft Exchange Server 2019 Cumulative Update 3affected: unspecifiedCVE List
  • Microsoft Exchange Server 2016 Cumulative Update 14affected: unspecifiedCVE List
  • Microsoft Exchange Server 2016 Cumulative Update 15affected: unspecifiedCVE List
  • Microsoft Exchange Server 2019 Cumulative Update 4affected: unspecifiedCVE List
  • Microsoft Exchange Server 2010 Service Pack 3 Update Rollup 30affected: unspecifiedCVE List

References 4