Vendor: SonicWall
Vendor URL: https://www.sonicwall.com/
Versions affected: 10.2.0.8-37sv, 10.2.1.1-19sv
Systems Affected: SMA 100 Series (SMA 200, 210, 400, 410, 500v)
Author: Richard Warren <richard.warren[at]nccgroup[dot]trust>
Advisory URL: https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0026
CVE Identifier: CVE-2021-20044
Risk: CVSS 7.2 (High)

Summary

SonicWall SMA 100 Series appliances running firmware versions 10.2.0.8-37sv, 10.2.1.1-19sv suffer from a post-authenticated command injection vulnerability, which can be exploited to execute arbitrary commands with root privileges.

The vulnerability exists in the Python management API, which is exposed remotely via HTTP, and is accessible to authenticated administrative users. When restoring system settings, an attacker can inject arbitrary commands via various means, resulting in code execution as root.

An attacker could chain other issues patched in this update, such as Arbitrary File Deletion or Stored XSS, to achieve Remote Code Execution from an unauthenticated perspective.

Impact

An attacker that successfully exploits this issue will be able to execute code on the underlying Operating System with the privileges of the root user.

Recommendation

Upgrade to SMA version 10.2.0.9-41sv, 10.2.1.3-27sv or above.

Vendor Communication

2021-10-29 - Vulnerability reported to SonicWall PSIRT.
2021-11-02 - Acknowledgement from SonicWall PSIRT.
2021-12-01 - SonicWall request that NCC Group withhold technical details until 2022-01-11, releasing high-level advisories on 2021-12-09.
2021-12-03 - NCC Group agrees to suggested disclosure timeline.
2021-12-07 - Patch released and SonicWall publish KB article and security advisory.
2021-12-09 - NCC Group advisory released.

Thanks to

Jennifer Fernick and Aaron Haymore from NCC Group for their assistance with disclosure.

About NCC Group

NCC Group is a global expert in cybersecurity and risk mitigation, working with businesses to protect their brand, value and reputation against the ever-evolving threat landscape. With our knowledge, experience and global footprint, we are best placed to help businesses identify, assess, mitigate & respond to the risks they face. We are passionate about making the Internet safer and revolutionizing the way in which organizations think about cybersecurity.

Published Date: 2021-12-09

Written By: Richard Warren

Published