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CVE-2021-20021: SonicWall Email Security Improper Privilege Management Vulnerability
SonicWall SonicWall Email Security · in CISA KEV since 2021-11-03
2021-11-03added to KEV
2021-11-17federal remediation due date
83.43%EPSS exploit probability (30 days) 99.7th percentile
9.8 CRITICALCVSS 3.1
Knownknown ransomware use
208days from NVD publication to KEV
What it is
SonicWall Email Security contains an improper privilege management vulnerability that allows an attacker to create an administrative account by sending a crafted HTTP request to the remote host. This vulnerability has known usage in a SonicWall Email Security exploit chain along with CVE-2021-20022 and CVE-2021-20023 to achieve privilege escalation.
Required action (CISA)
Apply updates per vendor instructions.
| CWE | CWE-306 |
|---|---|
| CVSS vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD published | 2021-04-09 (Analyzed) |
Original records: NVD · CISA KEV · JSON: /api/cve/CVE-2021-20021.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.