CVE-2026-20893

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{}

{"analysis": {"en": {"generated_at": "2026-04-18T08:10:16.037540+00:00", "value": {"mitigation_remediation": ["Upgrade to a version newer than 2.0.25.0 where the origin validation flaw is fixed.", "Restrict local user accounts that can log in to the system hosting AuthConductor Client Basic, limiting the attack surface for local privilege escalation.", "Configure the AuthConductor Client Basic service to run with the least privileges required, avoiding SYSTEM level access when possible."], "summary": {"action": "Immediate Patch", "impact": "Execute arbitrary code with SYSTEM privilege"}, "threat_synthesis": {"affected_systems": "The vulnerability affects Fujitsu Client Computing Limited\u2019s AuthConductor Client Basic V2 product; versions 2.0.25.0 and earlier are impacted. Upgrading to a newer release should remediate the issue.", "description_and_impact": "An origin validation error in Fujitsu Security Solution AuthConductor Client Basic V2 allows an attacker who can log in to the Windows system to execute arbitrary code with SYSTEM privilege and modify registry values. The flaw is a trust boundary violation (CWE\u2011346), providing broad impact on confidentiality, integrity, and availability of the affected machine.", "risk_and_exploitability": "The CVSS score of 8.5 indicates high severity, but the EPSS score is below 1% and the vulnerability is not listed in the CISA KEV catalog, suggesting a low likelihood of widespread exploitation. The likely attack vector requires local access; an adversary who can log in to the Windows system where the product runs can trigger the flaw, then achieve SYSTEM privileges or alter critical registry settings."}}}}, "created": "2026-01-07T10:08:04.203216+00:00", "title": "Origin Validation Error Allows SYSTEM Privilege Execution in Fujitsu AuthConductor Client Basic V2", "updated": "2026-04-18T08:15:15.892155+00:00", "vendors": ["fujitsu", "fujitsu$PRODUCT$security_solution_authconductor_client_basic_v2", "microsoft", "microsoft$PRODUCT$windows"]}