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CVE

CVE-2021-31209

Microsoft Exchange Server Spoofing Vulnerability

Microsoft Exchange Server Spoofing Vulnerability.

MEDIUM · CVSS 6.5 EPSS 0.00649
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-290Authentication Bypass by Spoofing
▤

Affected Products & Versions

1
microsoft exchange serverall versions
▣

Scoring & Timeline

6.5
MEDIUM · CVSS v3.1 · secure@microsoft.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD11 May 2021 · 07:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
SSVC triage · cisa-vulnrichment
Exploitation
none
Automatable
no
Technical impact
partial
SSVC asks the questions that actually drive patch urgency: is it being exploited, can attacks be automated, and how total is the impact.
⚑

Vendor Advisories

1
msrcCVE-2021-31209Spoofing
🔗

References & Sources

2
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31209PatchVendor Advisory
https://www.zerodayinitiative.com/advisories/ZDI-21-615/Third Party AdvisoryVDB Entry
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