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CVE-2021-20021: SonicWall Email Security Improper Privilege Management Vulnerability

CVE-2021-20021 is rated critical with a CVSS v3.1 base score of 9.8 and affects SonicWall SonicWall Email Security, along with 10 other products in NVD’s configuration data. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available. CISA added it to its Known Exploited Vulnerabilities catalog on 2021-11-03, which means exploitation in the wild has been observed.

Vulnerability description

A vulnerability in the SonicWall Email Security version 10.0.9.x allows an attacker to create an administrative account by sending a crafted HTTP request to the remote host.

Severity breakdown

CVSS v3.1 9.8: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

  • Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
  • Attack complexity: Low. No special conditions; the attack can be repeated reliably.
  • Privileges required: None. No account or prior access is needed.
  • User interaction: None. No action from any user is needed.
  • Scope: Unchanged. Impact stays within the vulnerable component.
  • Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
  • Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
  • Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-269: Improper Privilege Management

The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor.

Affected products

  • Sonicwall Email Security: before 10.0.9.6103
  • Sonicwall Email Security Appliance 9000 Firmware: before 10.0.9.6105
  • Sonicwall Email Security Appliance 3300 Firmware: before 10.0.9.6105
  • Sonicwall Email Security Appliance 4300 Firmware: before 10.0.9.6105
  • Sonicwall Email Security Appliance 8300 Firmware: before 10.0.9.6105
  • Sonicwall Email Security Appliance 5000 Firmware: before 10.0.9.6105
  • Sonicwall Email Security Appliance 7000 Firmware: before 10.0.9.6105
  • Sonicwall Email Security Appliance 5050 Firmware: before 10.0.9.6105
  • Sonicwall Email Security Appliance 7050 Firmware: before 10.0.9.6105
  • Sonicwall Email Security Virtual Appliance: before 10.0.9.6105
  • Sonicwall Hosted Email Security: before 10.0.9.6103

References