ZeroDay Findings
Sign inSign up

Vulnerabilities

Vulnerability · CVE-2021-31196

Microsoft Exchange Server Information Disclosure Vulnerability

Published Jul 14, 2021 · catalog updated Aug 10, 2026 · Microsoft Exchange Server

Patch now

CVE-2021-31196 is in the CISA known-exploited catalog, due Sep 11, 2024. Confirm Microsoft Exchange Server against the vendor advisory and apply that fix. The CVSS score does not change the priority.

Gaps on this record

  • No version range is stored. A customer cannot check an installed version against this record.
Severity
High7.2
Known exploitation
CISA KEV and VulnCheck KEV
EPSS
54.06%
Remediation
Remediation guidance
Affected products
cpe microsoft/exchange server · vendor Microsoft Exchange Server

Microsoft Exchange Server contains an information disclosure vulnerability that allows for remote code execution.

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • cpe microsoft/exchange server2013
  • cpe microsoft/exchange server2016
  • cpe microsoft/exchange server2019
  • vendor Microsoft Exchange Serverversion unspecified

How to fix CVE-2021-31196

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

CVE-2021-31196 is in the CISA known-exploited catalog, due Sep 11, 2024. Confirm Microsoft Exchange Server against the vendor advisory and apply that fix. The CVSS score does not change the priority.

Which versions are affected?

Compare what you have installed with microsoft/exchange server 2013; microsoft/exchange server 2016; microsoft/exchange server 2019. Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

What should an analyst verify?

No weakness class is stored. EPSS 54.06%. The CISA KEV listing is the exploitation evidence. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Jul 14, 2021 · Catalog

    Detected

    Microsoft Exchange Server contains an information disclosure vulnerability that allows for remote code execution.

  2. Aug 21, 2024 · CISA KEV

    Known exploited

    Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

  3. Sep 11, 2024 · CISA KEV

    Remediation due

    Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

  4. Aug 10, 2026 · Catalog

    Updated

    Microsoft Exchange Server contains an information disclosure vulnerability that allows for remote code execution.

Sources

  • CISA KEVConfirmed exploitationCVE-2021-31196

    Microsoft Exchange Server contains an information disclosure vulnerability that allows for remote code execution.

    cisa.gov
  • CVE.orgVulnerability recordCVE-2021-31196

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2021-31196

    30-day exploitation probability 54.1%

    first.org
  • NIST NVDVulnerability recordCVE-2021-31196

    Microsoft Exchange Server Remote Code Execution Vulnerability

    nvd.nist.gov
  • VulnCheck KEVConfirmed exploitationCVE-2021-31196

    Microsoft Exchange Server contains an information disclosure vulnerability that allows for remote code execution.

    vulncheck.com

References

Freshness

Last verified in this catalog Oct 17, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.