CVE-2021-31196: Microsoft Exchange Server Information Disclosure Vulnerability

CVE-2021-31196 · Severity: critical · CVSS 7.2 · Exploited in the wild · Published 2024-08-21

Microsoft Exchange Server contains a vulnerability that can lead to information disclosure or remote code execution. The flaw allows an authenticated attacker with high privileges to compromise the confidentiality, integrity, and availability of the system over a network.

Technologies: Microsoft Exchange Server. Vendors: Microsoft.

Quick answers

Is CVE-2021-31196 exploited in the wild?
Yes. CVE-2021-31196 is known to be exploited in the wild, first recorded on 21 August 2024. Treat it as urgent.
How severe is CVE-2021-31196?
Critical severity, with a CVSS score of 7.2, published 21 August 2024.
Which products and versions are affected?
Microsoft Exchange Server 2013 Cumulative Update 23; Microsoft Exchange Server 2016 Cumulative Update 20; Microsoft Exchange Server 2016 Cumulative Update 21; Microsoft Exchange Server 2019 Cumulative Update 9; and 1 more.
Is there a fix for CVE-2021-31196?
A patch was published on 2021-07-16: Initial analysis and patch references added by NIST/Microsoft Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2021-31196 attacked?
It is attacked over the network, in a hosted service.
Am I affected by CVE-2021-31196?
Check whether you run Microsoft Exchange Server. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Affected products

  • Microsoft Exchange Server 2013 Cumulative Update 23
  • Microsoft Exchange Server 2016 Cumulative Update 20
  • Microsoft Exchange Server 2016 Cumulative Update 21
  • Microsoft Exchange Server 2019 Cumulative Update 9
  • Microsoft Exchange Server 2019 Cumulative Update 10

Timeline

  • 2021-07-14: disclosed: NVD Published Date
  • 2021-07-16: patched: Initial analysis and patch references added by NIST/Microsoft
  • 2024-08-21: kev added: Added to CISA Known Exploited Vulnerabilities Catalog
  • 2024-08-21: exploited: Reported as exploited in the wild per CISA KEV entry

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