CVE-2026-73874 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 low privileged attacker with network access via HTTP to compromise Helidon. Successful attacks of this vulnerability can result in unauthorized update, insert or delete access to some of Helidon accessible data as well as unauthorized read access to a subset of Helidon accessible data. CVSS 3.1 Base Score 5.4 (Confidentiality and Integrity impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/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 significant risk to organizations relying on this framework for building microservices and cloud-native applications in Java environments. The core issue stems from insufficient input validation or access control mechanisms within the HTTP request handling logic of the web server. As indicated by the vulnerability profile, it allows an attacker with low privileges and network access via standard HTTP protocols to exploit these weaknesses. This classification highlights that while the attacker does not require high-level system credentials, they must have some form of authenticated or authorized connection to the service, which is a common scenario in internal enterprise networks where Helidon services are typically deployed.
The technical nature of this flaw enables unauthorized modifications and disclosures of data accessible through the Helidon application. Specifically, successful exploitation permits an attacker to perform unauthorized update, insert, or delete operations against certain datasets managed by the server. Furthermore, it grants unauthorized read access to a subset of the same data. This dual impact on both integrity and confidentiality suggests that the vulnerability likely involves improper authorization checks when processing specific HTTP methods such as POST, PUT, DELETE, or potentially even GET requests depending on the underlying implementation details. The ability to alter database records or application state without proper verification constitutes a critical breach of security principles, allowing malicious actors to manipulate business logic, corrupt data integrity, and extract sensitive information that should remain restricted.
From an operational perspective, this vulnerability poses substantial risks to the confidentiality, integrity, and availability of enterprise applications built on Helidon 4.5.0. The CVSS 3.1 base score of 5.4 reflects a medium severity level, driven by local network access requirements but mitigated somewhat by the need for low-privileged authentication rather than full administrative rights. However, in many modern microservices architectures, services often communicate with each other using service accounts that may have broader permissions than typical end-user accounts. Consequently, an attacker who compromises one service could leverage this vulnerability to pivot and affect downstream data stores or dependent services. The impact includes potential financial loss due to fraudulent transactions if the affected data involves financial records, reputational damage from public data leaks, and regulatory non-compliance with standards such as GDPR or HIPAA that mandate strict access controls over personal health information or personally identifiable information.
This vulnerability aligns closely with CWE-862 Missing Authorization, where an application fails to enforce proper checks on user privileges before allowing actions on resources. Additionally, it relates to CWE-918 Server-Side Request Forgery if the flaw involves manipulating internal requests, though the primary vector described is direct HTTP exploitation. In terms of MITRE ATT&CK mapping, this activity corresponds to techniques involving Application Layer Protocol Manipulation and potentially Data Injection or Exfiltration depending on how the attacker leverages the unauthorized write access. The attack path typically involves crafting malicious HTTP payloads that bypass existing security filters or exploit logic errors in request parsing routines within the Imperative Web Server module.
To mitigate this risk, immediate action is required to update Helidon to a patched version where these authorization checks have been reinforced. Organizations should also implement defense-in-depth strategies by placing reverse proxies such as NGINX or Apache HTTP Server in front of Helidon instances to enforce additional access control policies and rate limiting. Web Application Firewalls can be configured to detect and block anomalous HTTP patterns associated with this exploitation vector. Furthermore, developers must review the application code for any custom handlers that interact directly with data stores without adequate validation against current user roles or permissions. Regular security audits and static analysis tools should be employed to identify similar authorization gaps in other parts of the Helidon-based applications before they can be exploited by adversaries seeking to compromise enterprise infrastructure.