November 3, 2021 · Applied Cybernetics Group
CVE-2021-20023 SonicWall SonicWall Email Security
known ransomware use
SonicWall Email Security Path Traversal Vulnerability
- Added to KEV
2021-11-03- Federal due date
2021-11-17- Vendor
- SonicWall
- Product
- SonicWall Email Security
- EPSS
- 99.0th percentile (score 0.517, as of
2026-11-06) - NVD CVSS v3.1
- 4.9 (MEDIUM)
- Ransomware use
- Known
- Upstream
- https://nvd.nist.gov/vuln/detail/CVE-2021-20023
CISA short description
SonicWall Email Security contains a path traversal vulnerability that allows a post-authenticated attacker to read files on the remote host. This vulnerability has known usage in a SonicWall Email Security exploit chain along with CVE-2021-20021 and CVE-2021-20022 to achieve privilege escalation.
Required action
Apply updates per vendor instructions.
NVD 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.