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TI-2026-47176 Aliases CVE-2026-66420GHSA-fcvp-v754-r7rh

MeshCentral Cross-Site WebSocket Hijacking via Origin Validation Bypass on Self-Signed Certificate Deployments

Priority LOW 39CWE-346Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Active
Attack complexity
Low
Attack requirements
None
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-346.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00221 12th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
YlianstMeshCentral1.1.21 and later—No fix listedCNA
  • MeshCentral VendorYlianst Affected 1.1.21 and later Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-66420
  2. 2026-10-03 Alias added: GHSA-fcvp-v754-r7rh

References

Patch 2

Other 1

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences