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CVE-2021-20023

Published: Apr 20, 2021Updated: Nov 12, 2025 Sources: CVE List NVD BDUCWE-22
NVD MITRE
4.9CVSSMEDIUM
EPSS Score
51.4%
Top 1.2%
CISA KEV
Active Exploitation
Since Nov 3, 2021
Exploits
No Known Exploits
Remediation
Patch Available

Description

SonicWall Email Security version 10.0.9.x contains a vulnerability that allows a post-authenticated attacker to read an arbitrary file on the remote host.

CVSS Vector Breakdown

AV:NAC:LPR:HUI:NS:UC:HI:NA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:HPrivileges Required
High
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:NIntegrity
None
A:NAvailability
None
Open in CVSS calculator →

Weaknesses

CWE-22

Affected Products

email securitysonicwallNetworking Infrastructure
email security appliance 9000 firmwaresonicwallNetworking Infrastructure
email security appliance 3300 firmwaresonicwallNetworking Infrastructure
email security appliance 4300 firmwaresonicwallNetworking Infrastructure
email security appliance 8300 firmwaresonicwallNetworking Infrastructure
sonicwallcommercialUSNetworking Infrastructureaka sonicwall
and 8 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

CISA Known Exploited Vulnerability
Added to KEV:Nov 3, 2021
Remediation due:Nov 17, 2021
Ransomware:Known ransomware use

Required action: Apply updates per vendor instructions.

Official Patch Available

MITRE ATT&CK

2 techniques
Collection
Discovery
View detailed technique mapping

References

https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0010
psirt.global.sonicwall.com
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-20023
cisa.gov
https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0010
psirt.global.sonicwall.com
and 2 more references View all →

Timeline

Published
Apr 20, 2021
Added to CISA KEV
Nov 3, 2021
Last Updated
Nov 12, 2025

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