CVE-2021-20023

MEDIUM4.9

CISA KEV

Published 2021-04-20 · Updated 2026-10-01 · Source PSIRT@sonicwall.com

Summary

CVE-2021-20023 is a medium-severity (CVSS 4.9) vulnerability in SonicWall SonicWall Email Security. CISA added it to the Known Exploited Vulnerabilities catalog on November 3, 2021, which means exploitation in the wild has been confirmed; US federal agencies had to remediate it by November 17, 2021. CISA also lists it as known to be used in ransomware campaigns, so it should be prioritised accordingly. SonicWall has 19 vulnerabilities in the KEV catalog, 13 of them linked to ransomware.

All 19 known-exploited SonicWall vulnerabilities →

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: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N

CWE-22CWE-22

CISA Known-Exploited Vulnerability

Product: SonicWall — SonicWall Email Security

Name: SonicWall Email Security Path Traversal Vulnerability

Date added: 2021-11-03 · Due: 2021-11-17

USED IN RANSOMWARE

Required action: Apply updates per vendor instructions.

References

View on NVD

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