Critical 10.0Published Dec 5, 2025

CVE-2025-34256Advantech WISE-DeviceOn Server < 5.4 Hard-coded JWT Key Authentication Bypass

Updated under an hour ago (Oct 27, 2026, 2:10 AM ET)

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It affects Advantech Co., Ltd. WISE-DeviceOn Server and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Advantech Co., Ltd. WISE-DeviceOn Server

Exploited in the last 30 days

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.

CVSS: 10.0 CRITICAL (v4.0, CNA)CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
Weakness (CWE): CWE-321
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: VulnCheck
NVD analysis: Modified
Record last updated: Aug 14, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Advantech Co., Ltd. WISE-DeviceOn Server advantech:wise_deviceon_server (from the name)	before 5.4.0	CNA record
advantech wise-deviceon_server advantech:wise-deviceon_server	before 5.4	NVD

References

References

https://advcloudfiles.advantech.com/cms/2ca1b071-fd78-4d7f-8a2a-7b4537a95d19/Security%20Advisory%20PDF%20File/SECURITY-ADVISORY----DeviceOn-20251208-2.pdf	vendor-advisory, patch
https://pellera.com/blog/advantech-wise-deviceon-cve-2025-34256-vulnerability/	technical-description, exploit
https://docs.deviceon.advantech.com/docs/resource/	product
https://www.vulncheck.com/advisories/advantech-wise-deviceon-server-hardcoded-jwt-key-authentication-bypass	third-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.