CVE-2021-20023
medium CISA KEVSonicWall Email Security Path Traversal Vulnerability
Vendor / product: SonicWall — SonicWall Email Security
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
4.9
4.9 (CVSS v3.1)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N Severity source: NVD CVSS v3.1 (nvd@nist.gov)
Timeline (UTC)
Published: 2021-04-20 12:15
Modified: 2026-10-01 21:17
NVD status: Analyzed
Last synced 1 day ago
Verified against the source API 2026-10-27 07:07 UTC
Exploitation
Listed in CISA KEV
Added 2021-11-03 · due 2021-11-17
Known ransomware use: Known
Required action (CISA)
Apply updates per vendor instructions.
Affected products
sonicwall / email_security <10.0.9.6173
sonicwall / email_security_appliance_9000_firmware <10.0.9.6177
sonicwall / email_security_appliance_3300_firmware <10.0.9.6177
sonicwall / email_security_appliance_4300_firmware <10.0.9.6177
sonicwall / email_security_appliance_8300_firmware <10.0.9.6177
sonicwall / email_security_appliance_5000_firmware <10.0.9.6177
sonicwall / email_security_appliance_7000_firmware <10.0.9.6177
sonicwall / email_security_appliance_5050_firmware <10.0.9.6177
sonicwall / email_security_appliance_7050_firmware <10.0.9.6177
sonicwall / email_security_virtual_appliance <10.0.9.6177
sonicwall / hosted_email_security <10.0.9.6173
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
Vendor advisory: https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0010
Vendor advisory: https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0010
References
- https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0010 PSIRT@sonicwall.com
- https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0010 af854a3a-2127-422b-91ae-364da2661108
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-20023 134c704f-9b21-4f2e-91b3-4a467353bcc0
Data sources
CISA KEV — fetched 2026-10-27 06:50 UTC · record ↗
NVD CVE API 2.0 — fetched 2026-10-27 07:07 UTC · record ↗