What is CVE-2025-34256?

CVE-2025-34256 is a critical-severity vulnerability in Advantech Wise-deviceon_server, classified under Use of Hard-coded Cryptographic Key. CVSS score: 9.8/10. Published 2025-12-05.

How severe is CVE-2025-34256?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Vulnerability in Advantech Wise-deviceon_server

CVE-2025-34256

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 tha…

EPSS: 0.006 (43.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Advantech Wise-deviceon_server
Advantech Co., Ltd. Wise-deviceon Server — versions 0

Weakness classification (CWE)

CWE-321 — Use of Hard-coded Cryptographic Key

References

disclosure@vulncheck.com (vendor-advisory, patch)
disclosure@vulncheck.com (technical-description, exploit)
disclosure@vulncheck.com (Product, product)
disclosure@vulncheck.com (Third Party Advisory, third-party-advisory)

Frequently asked questions

What is CVE-2025-34256?: CVE-2025-34256 is a critical-severity vulnerability in Advantech Wise-deviceon_server, classified under Use of Hard-coded Cryptographic Key. CVSS score: 9.8/10. Published 2025-12-05.
How severe is CVE-2025-34256?: Critical severity. CVSS v3 base score is 9.8 out of 10.