CVE-2026-66152: CWE-29 Path traversal: '\..\filename' in SonicWall NetExtender

This vulnerability (CVE-2026-66152) involves a path traversal issue (CWE-29) in the SonicWall NetExtender Linux client file extractor. An attacker can leverage the '\..\filename' path traversal to write arbitrary files as root, potentially leading to full system compromise. The vulnerability affects SonicWall NetExtender versions 10.3.5 and earlier. The CVSS 3.1 base score is 8.8, reflecting network attack vector, low attack complexity, no privileges required, user interaction required, unchanged scope, and high impact on confidentiality, integrity, and availability.

Successful exploitation allows an attacker to write arbitrary files with root privileges on the affected system. This can lead to full system compromise, including unauthorized code execution, data modification, and denial of service. The vulnerability impacts confidentiality, integrity, and availability at a high level.

No patch or official fix information is currently provided. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, users should consider restricting access to the NetExtender client and monitor for suspicious activity related to file extraction. Avoid running the client with elevated privileges if possible.