CVE-2025-34256

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La explotaci\u00f3n exitosa permite el control total como administrador de la instancia de DeviceOn y puede ser aprovechada para ejecutar c\u00f3digo en agentes gestionados a trav\u00e9s de las funciones de gesti\u00f3n remota de DeviceOn."}], "id": "CVE-2025-34256", "lastModified": "2026-06-17T09:13:45.107", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 9.8, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.9, "source": "nvd@nist.gov", "type": "Primary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 10.0, "baseSeverity": "CRITICAL", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "HIGH", "subConfidentialityImpact": "HIGH", "subIntegrityImpact": "HIGH", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "version": "4.0", "vulnAvailabilityImpact": "HIGH", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "disclosure@vulncheck.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2025-34256", "options": [{"exploitation": "poc"}, {"automatable": "yes"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-04-15T19:36:16.430752Z", "version": "2.0.3"}}]}, "published": "2025-12-05T18:15:55.053", "references": [{"source": "disclosure@vulncheck.com", "url": "https://advcloudfiles.advantech.com/cms/2ca1b071-fd78-4d7f-8a2a-7b4537a95d19/Security%20Advisory%20PDF%20File/SECURITY-ADVISORY----DeviceOn-20251208-2.pdf"}, {"source": "disclosure@vulncheck.com", "tags": ["Product"], "url": "https://docs.deviceon.advantech.com/docs/resource/"}, {"source": "disclosure@vulncheck.com", "url": "https://pellera.com/blog/advantech-wise-deviceon-cve-2025-34256-vulnerability/"}, {"source": "disclosure@vulncheck.com", "tags": ["Third Party Advisory"], "url": "https://www.vulncheck.com/advisories/advantech-wise-deviceon-server-hardcoded-jwt-key-authentication-bypass"}], "sourceIdentifier": "disclosure@vulncheck.com", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-321"}], "source": "disclosure@vulncheck.com", "type": "Secondary"}]}

{}

{"analysis": {"en": {"generated_at": "2026-04-20T16:40:58.802319+00:00", "value": {"mitigation_remediation": ["Apply the vendor\u2011provided patch to upgrade to version 5.4 or later.", "If a patch cannot be applied immediately, limit DeviceOn API access to trusted network segments or use firewall rules to block external traffic.", "Reconfigure the server to reject any JWTs that do not contain both a valid email and a correctly signed claim, or replace the hard\u2011coded secret with a unique, per\u2011installation key."], "summary": {"action": "Immediate Patch", "impact": "Remote Code Execution"}, "threat_synthesis": {"affected_systems": "Advantech Company Ltd. \u2013 WISE\u2011DeviceOn Server; all installations running any version older than 5.4 are affected. No specific patch version is listed, but the fix requires upgrading to at least version 5.4 or applying the vendor\u2019s latest security update.", "description_and_impact": "Advantech WISE\u2011DeviceOn Server versions before 5.4 contain a hard\u2011coded HS512 HMAC secret that signs all EIRMMToken JWTs. Because the server accepts JWTs that contain only a valid email claim, a remote unauthenticated attacker can forge a token for any account, including the super admin. The attacker then obtains full administrative control of the DeviceOn instance and can use the server\u2019s remote management features to execute code on managed agents. The vulnerability is a CWE\u2011321 weakness related to hard\u2011coded cryptographic keys, compromising both confidentiality and integrity of authentication tokens.", "risk_and_exploitability": "The CVSS score of 10 indicates critical severity, while the EPSS score is less than 1% and the vulnerability is not listed in the CISA KEV catalog, indicating that active exploitation is currently unlikely but possible. Based on the description, the attack vector is a remote, unauthenticated network request to the device\u2019s API that accepts forged JWTs. Once a valid token is forged, the attacker gains full administrative privileges and can run arbitrary code through remote management capabilities. Because the exploit relies solely on the hard\u2011coded key and the server\u2019s lax validation, it can be performed without any credentials or local access."}}}}, "created": "2025-12-05T20:56:04.303482+00:00", "updated": "2026-04-20T16:45:11.954669+00:00", "vendors": ["advantech", "advantech$PRODUCT$wise-deviceon"]}