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Findings

CVE-2021-31196

Microsoft Exchange Server Information Disclosure Vulnerability

Published Jul 14, 2021 · corrected/updated Aug 10, 2026 · microsoft exchange server · evidence confidence very high

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

Grounded briefings

Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.

Executive

CVE-2021-31196 is a high public vulnerability record for microsoft exchange server. CISA lists it as known exploited. Published remediation guidance: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.

System administrator

Identify whether microsoft exchange server is in your estate, then compare installed versions with the affected ranges. Affected packages or ranges on record: microsoft/exchange server (2013); microsoft/exchange server (2016); microsoft/exchange server (2019); Microsoft Exchange Server. Published remediation guidance: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.

Security analyst

Signals on file: CVSS 7.2, EPSS 54.1%. CISA lists it as known exploited. Sources contributing to this record: cisa_kev, cve_org, epss, nvd. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.

Exploitation and remediation

  • Exploitation evidence

    Confirmed in CISA KEV since Aug 21, 2024. Listed in the CISA Known Exploited Vulnerabilities catalog.

  • Patch and remediation

    Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. CISA due date Sep 11, 2024.

  • Safe detection guidance

    Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.

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.

Affected

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

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

References