23 Oct 2026 15:48:27 UTC
MeshCentral Cross-Site WebSocket Hijacking via Origin Validation Bypass on Self-Signed Certificate Deployments
cve-program · CVE-2026-66420 · Published
CVE-2026-66420
MeshCentral Cross-Site WebSocket Hijacking via Origin Validation Bypass on Self-Signed Certificate Deployments
CVSS 4.0 8.6 HIGHCVSS 3.1 8.8 HIGHCheck source for fixed versionsKEV status unknown
cve-program · CVE-2026-66420
PublishedMeshCentral 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.
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Exploitation and risk
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