CVE-2021-33766
Description
Microsoft Exchange Server Information Disclosure Vulnerability
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:LConfidentialityLow
I:LIntegrityLow
A:LAvailabilityLow
Weaknesses
Affected Products
and 2 more affected products View all →
Exploitability
CISA Known Exploited Vulnerability
Added to KEV:Jan 18, 2022
Remediation due:Feb 1, 2022
Required action: Apply updates per vendor instructions.
Official Patch Available
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References
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-33766
portal.msrc.microsoft.com
https://www.zerodayinitiative.com/advisories/ZDI-21-798/
zerodayinitiative.com
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-33766
cisa.gov
and 3 more references View all →
Timeline
Published
Jul 14, 2021
Added to CISA KEV
Jan 18, 2022
Last Updated
Oct 29, 2025
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