CVE-2021-31207
Microsoft Exchange Server Security Feature Bypass Vulnerability
- Published
- May 11, 2021
- Updated
- Oct 21, 2025
- Assigning CNA
- microsoft
- Evidence observed
- Nov 3, 2021
Primary CVSS
nvd · CVSS 3.1
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:HHigh · next 30 days
- Percentile
- 100.0%
- Model date
- Sep 21, 2026
EPSS is a statistical estimate, not a certainty or a measure of impact. Combine it with CVSS, KEV status, exposure and your environment.
CISA Known Exploited
This CVE appears in the CISA Known Exploited Vulnerabilities catalog.
Summary
Microsoft Exchange Server Security Feature Bypass Vulnerability
Sources
5- proxyshellExploit
Proof of Concept for CVE-2021-34473, CVE-2021-34523, and CVE-2021-31207
- ProxyVulnsExploit
[ProxyLogon] CVE-2021-26855 & CVE-2021-27065 Fixed RawIdentity Bug Exploit. [ProxyOracle] CVE-2021-31195 & CVE-2021-31196 Exploit Chains. [ProxyShell] CVE-2021-34473 & CVE-2021-34523 & CVE-2021-31207 Exploit Chains.
- ProxyShell_POCScanner
POC for scanning ProxyShell(CVE-2021-34523,CVE-2021-34473,CVE-2021-31207)
Responsible use
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