CVE-2026-54365
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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.22%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 4.0
- 8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.22% probability · 12th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-306
- Source
- disclosure@vulncheck.com
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.