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CVE-2021-33766: Microsoft Exchange Server Information Disclosure
Microsoft Exchange Server · in CISA KEV since 2022-01-18
2022-01-18added to KEV
2022-02-01federal remediation due date
98.14%EPSS exploit probability (30 days) 99.9th percentile
7.3 HIGHCVSS 3.1
Unknownknown ransomware use
188days from NVD publication to KEV
What it is
Microsoft Exchange Server contains an information disclosure vulnerability which can allow an unauthenticated attacker to steal email traffic from target.
Required action (CISA)
Apply updates per vendor instructions.
| CWE | CWE-287 |
|---|---|
| CVSS vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L |
| NVD published | 2021-07-14 (Analyzed) |
Original records: NVD · CISA KEV · JSON: /api/cve/CVE-2021-33766.json · all KEV CVEs
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Get the full file: Exploited Vulnerabilities Brief – September 2026 ($29): this month's KEV additions ranked by EPSS, ransomware use and due date, ready to hand to a patch team. Checkout by Polar.
Get the full file: Exploited Vulnerabilities Brief – September 2026 ($29): this month's KEV additions ranked by EPSS, ransomware use and due date, ready to hand to a patch team. Checkout by Polar.