Microsoft Exchange Server Information Disclosure Vulnerability
Microsoft — Microsoft Exchange Server 2019 Cumulative Update 9
Microsoft Exchange Server Remote Code Execution Vulnerability
7.2
46.4%
Vector breakdown
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- High
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
- Published
- Jul 14, 2021
- Modified
- Jan 12, 2026
- Added to KEV
- Aug 21, 2024
- Federal patch due
- Sep 11, 2024
CISA required action
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Proof-of-concept & exploitation references
Weaponization
Public repositories whose name or description references CVE-2021-31196, found via a live GitHub search at request time. These are community-sourced signals, not a verified working exploit - cross-check each one before relying on it, and treat higher star counts and recent activity as (weak) corroboration, not proof.
No public GitHub repositories referencing CVE-2021-31196 were found at last check. Absence here is not proof no exploit exists - see the references below for vendor advisories and write-ups.
References
Frequently asked questions
What is CVE-2021-31196?
Microsoft Exchange Server Remote Code Execution Vulnerability
How severe is CVE-2021-31196?
CVE-2021-31196 has a CVSS base score of 7.2 out of 10 (CVSS 3.1).
Is CVE-2021-31196 actively exploited in the wild?
Yes. CVE-2021-31196 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added Aug 21, 2024, meaning CISA has confirmed evidence of active exploitation.
What is the EPSS score for CVE-2021-31196?
46.4% - meaning FIRST.org's EPSS model estimates a 46.4% probability this vulnerability will be exploited in the wild within 30 days (99% percentile among all scored CVEs).
Cross-checked against
Impactr finds and proves whether CVE-2021-31196 - or flaws like it - are actually reachable in your own web apps and APIs, with a reproducible exploit as evidence.
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