# CVE-2026-66146: SonicWall GMS cross-site scripting

Source: https://junglewise.ai/threats/cve-2026-66146-sonicwall-gms-cross-site-scripting  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-11. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-66146 · Severity: medium · CVSS 6.1 · Published 2026-08-11

SonicWall GMS is a centralized management platform for security appliances. Multiple cross-site scripting vulnerabilities allow remote attackers to inject malicious scripts that execute in users' browsers, potentially leading to session hijacking, credential theft, or unauthorized administrative actions.

Technologies: [SonicWall GMS](https://junglewise.ai/threats/technologies/gms). Vendors: [SonicWall](https://junglewise.ai/threats/vendors/sonicwall).

## Quick answers

**Is CVE-2026-66146 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-66146 being exploited in the wild.

**How severe is CVE-2026-66146?** Medium severity, with a CVSS score of 6.1, published 11 August 2026.

**Which products and versions are affected?** SonicWall GMS 9.5.1 (Build 9510.1044) and earlier.

**Is there a fix for CVE-2026-66146?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-66146 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-66146?** Check whether you run SonicWall GMS at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

Multiple cross-site scripting (XSS) vulnerabilities exist in SonicWall GMS due to insufficient input validation or output encoding in the web interface. The vulnerabilities are reflected or stored XSS flaws that allow unauthenticated remote attackers to inject arbitrary JavaScript code. When a victim visits a malicious link or page, or accesses a compromised GMS instance, the injected script executes in their browser context with the privileges of their authenticated session. An attacker can steal session cookies, perform unauthorized administrative actions, or modify security policies.

## Affected products

- SonicWall GMS 9.5.1 (Build 9510.1044) and earlier

## Timeline

- 2026-08-11: disclosed

## References

- [https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2026-0011](https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2026-0011)

## Related threats

- [SonicWall GMS SQL injection](https://junglewise.ai/threats/cve-2026-109594-post-authentication-improper-neutralization-of-special-elements)
- [SonicWall GMS arbitrary file read](https://junglewise.ai/threats/cve-2026-109593-an-unauthenticated-attacker-with-network-access-to-the-sonicwall)
- [SonicWall GMS remote code execution via zipslip](https://junglewise.ai/threats/cve-2026-66145-sonicwall-gms-remote-code-execution-via-zipslip)