CVE-2026-66420 Details
Description
MeshCentral 1.1.21 contains a cross-site WebSocket hijacking protection bypass vulnerability that allows unauthenticated remote attackers to hijack authenticated administrator sessions by exploiting an unconditional early return in the CheckWebServerOriginName() function within webserver.js when self-signed certificates are in use. Attackers can open cross-origin WebSocket connections to any of the twelve WebSocket endpoints, send crafted action commands to exfiltrate the server sessionKey used to sign session cookies, forge session tokens as arbitrary users, and gain full remote control of all managed devices governed by the MeshCentral instance.
A vulnerability in MeshCentral version 1.1.21 allows unauthenticated remote attackers to bypass cross-site WebSocket hijacking protection. This is achieved by exploiting an unconditional early return in the CheckWebServerOriginName() function within webserver.js, specifically when self-signed certificates are used. The vulnerability enables attackers to hijack authenticated administrator sessions by opening cross-origin WebSocket connections to any of the twelve WebSocket endpoints. They can then send crafted action commands to exfiltrate the server sessionKey, which is used to sign session cookies, forge session tokens as arbitrary users, and gain full remote control of all managed devices under the affected MeshCentral instance.
Users can update to MeshCentral version 1.2.4 or later, where this vulnerability has been addressed.
Metrics
CVSS 4.0 Severity and Vector Strings:
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
CISA-ADP
Assessed Jul 31, 2026References to Advisories, Solutions, and Tools
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Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-346 | Origin Validation Error | [email protected] |
Affected Products
No affected product data is available for this CVE.
Change History
3 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jul 31, 2026 | CVE Modified | CISA-ADP |
| Jul 31, 2026 | CVE Modified | [email protected] |
| Jul 30, 2026 | New CVE Received | [email protected] |