Advantech WISE-DeviceOn Server < 5.4 Hard-coded JWT Key Authentication Bypass
Vulnerability Description
Advantech WISE-DeviceOn Server versions prior to 5.4 contain a hard-coded cryptographic key vulnerability. The product uses a static HS512 HMAC secret for signing EIRMMToken JWTs across all installations. The server accepts forged JWTs that need only contain a valid email claim, allowing a remote unauthenticated attacker to generate arbitrary tokens and impersonate any DeviceOn account, including the root super admin. Successful exploitation permits full administrative control of the DeviceOn instance and can be leveraged to execute code on managed agents through DeviceOn’s remote management features.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
Am I Vulnerable?
Launch our assessment wizard to check if your infrastructure is exposed to • CVE-2025-34256
Credits & Attribution
The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:
- Alex Williams from Pellera Technologies
References
- https://advcloudfiles.advantech.com/cms/2ca1b071-fd78-4d7f-8a2a-7b4537a95d19/Security%20Advisory%20PDF%20File/SECURITY-ADVISORY----DeviceOn-20251208-2.pdf
- https://pellera.com/blog/advantech-wise-deviceon-cve-2025-34256-vulnerability/
- https://docs.deviceon.advantech.com/docs/resource/
- https://www.vulncheck.com/advisories/advantech-wise-deviceon-server-hardcoded-jwt-key-authentication-bypass
More from Advantech Co., Ltd.
View All →Affected Vendor
Advantech Co., Ltd.
View all reports →