CVE-2026-73908 in Helidon
Summary
by MITRE • 08/19/2026
Vulnerability in the Helidon product of Oracle Fusion Middleware (component: Imperative Web Server). The supported version that is affected is 4.5.0. Easily exploitable vulnerability allows unauthenticated attacker with network access via HTTP to compromise Helidon. Successful attacks of this vulnerability can result in unauthorized access to critical data or complete access to all Helidon accessible data. CVSS 3.1 Base Score 7.5 (Confidentiality impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N).
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Analysis
by VulDB Data Team • 08/19/2026
The identified vulnerability resides within the Imperative Web Server component of Oracle Fusion Middleware Helidon, specifically affecting version 4.5.0. This security flaw represents a critical weakness in the application layer's handling of incoming HTTP requests, allowing for unauthorized access to sensitive data without requiring any form of authentication or user interaction. The nature of this vulnerability is consistent with CWE-287, which describes Improper Authentication, where an entity fails to adequately verify the identity of another entity before granting access to resources. In the context of Helidon's imperative programming model, this likely stems from a misconfiguration in route definitions or middleware that bypasses expected security checks for specific endpoints or request patterns. The vulnerability is easily exploitable by attackers who have network connectivity to the affected system, indicating a low barrier to entry and high risk of exploitation in internet-facing deployments.
From an operational perspective, the impact of this vulnerability is severe due to its direct effect on data confidentiality. As indicated by the CVSS 3.1 base score of 7.5, the primary consequence is High Confidentiality impact with no significant effects on Integrity or Availability. Successful exploitation allows an unauthenticated attacker to access critical business data stored within the Helidon application context. This could include personally identifiable information (PII), financial records, intellectual property, or other sensitive assets protected by regulatory frameworks such as GDPR or HIPAA depending on the industry sector. The ability to read all accessible data without detection poses a significant threat to organizational security posture and can lead to substantial reputational damage and legal liabilities.
The attack vector aligns with ATT&CK technique T1078, Valid Accounts, although in this specific case it involves unauthenticated access due to the failure of authentication mechanisms rather than stolen credentials. It also relates to T1530, Data from Local System, as the attacker gains direct read access to data handled by the application server. The simplicity of the exploit means that automated scanning tools and opportunistic attackers can easily identify and leverage this weakness across multiple instances if they are not properly segmented or secured behind additional network-level controls like Web Application Firewalls (WAF) with appropriate rule sets.
To mitigate this vulnerability, immediate action is required to patch the Helidon installation to a version where this flaw has been resolved by Oracle. In environments where patching cannot be performed immediately, administrators should implement strict access control lists at the network perimeter to restrict HTTP traffic to only trusted IP addresses if possible. Additionally, deploying a Web Application Firewall with rules that detect and block anomalous request patterns associated with unauthenticated data exfiltration can provide a layer of defense in depth. It is also crucial to review application code for any custom middleware or route configurations that might inadvertently disable authentication checks, ensuring that the principle of least privilege is enforced across all API endpoints. Regular security audits and penetration testing should be conducted to verify that such misconfigurations do not exist elsewhere in the Helidon deployment architecture.