Summary
CVE-2026-66147 is a critical, unauthenticated command injection vulnerability in the GMS Dispatcher Service of SonicWall Global Management System (GMS), affecting version 9.5.1 and all earlier releases on both Windows and Linux platforms. The flaw allows a remote, unauthenticated attacker to send specially crafted requests to the Dispatcher Service and achieve remote code execution (RCE). Given the network attack vector, lack of required authentication, and critical CVSS score of 9.4, this vulnerability poses a severe risk to any internet-exposed GMS deployment used to centrally manage SonicWall firewall fleets.
Technical details
- Root cause: Improper control of generation of code (CWE-94) within the GMS Dispatcher Service, which fails to adequately sanitize input before passing it to a command execution context.
- Trigger conditions: An attacker sends a specially crafted request to the exposed GMS Dispatcher Service; no valid credentials or user interaction are required.
- Attack vector: Network (remote), low attack complexity, no privileges required, no user interaction required.
- Impact: Successful exploitation results in remote code execution on the underlying host, which for a centralized management platform like GMS could enable an attacker to pivot into and control managed SonicWall firewall infrastructure. Per the CVSS vector, confidentiality impact is low while integrity and availability impacts are high, consistent with an RCE-class outcome.
Affected software
- SonicWall Global Management System (GMS) — version 9.5.1 and all earlier versions
- Affects both Windows and Linux platform builds of GMS
Severity
- CVSS v3.1 Base Score: 9.4 (Critical)
- Vector:
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H
Mitigation and recommended actions
- Immediate: No specific fixed/patched GMS build number has been published in the CVE record or SonicWall’s advisory (SNWLID-2026-0011) as of this writing. Security teams should monitor SonicWall’s PSIRT advisory page directly and MySonicWall for the release of a patched GMS build, and apply it as soon as it becomes available.
- If no patch is yet available:
- Do not expose the GMS Dispatcher Service directly to the internet; restrict access to trusted management networks only (VPN or internal segment).
- Place GMS management interfaces behind strict firewall ACLs limiting inbound access to known administrative IP ranges.
- Monitor GMS server logs and network traffic for anomalous or malformed requests to the Dispatcher Service.
- Consider isolating GMS instances on a dedicated management VLAN with no direct internet reachability until a patch is confirmed and applied.

