CVE-2026-54365

Description

CentreStack before 17.3 contains an unauthenticated deserialization vulnerability in GSNamespace.dll that allows unauthenticated attackers to create arbitrary local OS user accounts by supplying a crafted base64-encoded XML string to exposed API endpoints. Attackers can send a malicious StorageConfigure parameter to the jsonimportuserbyupn, jsonimportuserbyupnex, or japiimportuserbyupn endpoints to trigger InternalImportAdUserByUPN(), causing GladinetCloudMonitor.exe to invoke the NetUserAdd Windows API with attacker-controlled credentials and create arbitrary directories on the server filesystem.

CVSS Vector

References

• https://www.centrestack.com/
• https://www.vulncheck.com/advisories/centrestack-unauthenticated-user-creation-via-deserialization-in-gsnamespace-dll