CVE-2026-84197 in Ditto
Summary
by MITRE • 09/08/2026
In Eclipse Ditto's Node.js JavaScript client, all released versions of @eclipse-ditto/ditto-javascript-client-node from 2.0.0 to 3.9.0 and of its predecessor package @eclipse-ditto/ditto-javascript-client-node_1.0 from 1.0.0 to 2.1.0, the WebSocket transport hard-codes rejectUnauthorized: false when creating the underlying ws WebSocket. Certificate chain and hostname validation are therefore disabled for every wss:// connection, and no builder option, constructor argument or environment variable lets an application turn validation back on. An attacker in a position to intercept the connection can present an arbitrary certificate, complete the TLS handshake, read the credentials that the configured authentication provider sends in the Authorization header of the WebSocket upgrade request, and read, alter or inject Ditto Protocol messages for the lifetime of the connection. The Java client, the browser/DOM JavaScript client and the HTTP transport of the Node.js client are not affected.
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Analysis
by VulDB Data Team • 09/09/2026
The vulnerability identified within Eclipse Ditto's Node.js JavaScript client libraries represents a critical failure in Transport Layer Security (TLS) implementation, specifically affecting versions 2.0.0 through 3.9.0 of eclipse-ditto/ditto-javascript-client-node and its predecessor package eclipse-ditto/ditto-javascript-client-node_1.0 from version 1.0.0 to 2.1.0. This flaw stems from the hard-coding of the rejectUnauthorized option set to false during the initialization of the underlying WebSocket transport layer using the ws library. By disabling certificate validation, the application fails to verify that the server presenting a TLS certificate is indeed the legitimate entity it claims to be. Consequently, any attempt to establish a secure connection over wss:// proceeds without validating the certificate chain or checking if the hostname matches the certificate's subject alternative names. This configuration effectively strips away one of the primary defenses against network-based attacks, leaving the communication channel vulnerable to interception and manipulation by malicious actors capable of positioning themselves between the client and the server.
From a technical perspective, this misconfiguration aligns with CWE-295 Improper Certificate Validation, as the application does not properly validate certificates or hostnames during TLS negotiation. The absence of any builder option, constructor argument, or environment variable to re-enable validation means that developers cannot mitigate this issue through standard configuration changes within the library's API. This rigidity forces applications relying on these specific versions to either upgrade immediately if a fixed version is available or implement complex workarounds at the application level, which may not be feasible depending on how deeply the client libraries are integrated into the system architecture. The vulnerability persists across all released versions in the specified ranges, indicating a systemic design oversight rather than an isolated coding error that could have been patched with a simple configuration toggle.
The operational impact of this vulnerability is severe, as it enables Man-in-the-Middle (MitM) attacks where an attacker can intercept the WebSocket connection and present an arbitrary certificate to complete the TLS handshake successfully. Once the encrypted channel is established under false pretenses, the attacker gains full visibility into the traffic flowing between the client and the Eclipse Ditto backend. This includes the ability to read sensitive credentials transmitted in the Authorization header of the WebSocket upgrade request, which are typically used for authentication with an external identity provider or internal security service. Furthermore, because the integrity of the connection is not guaranteed by valid certificate validation, attackers can also modify or inject arbitrary Ditto Protocol messages into the stream without detection. This compromises both confidentiality and integrity, allowing unauthorized access to device data, control signals, and system configurations managed by Eclipse Ditto.
This scenario maps directly to several tactics within the MITRE ATT&CK framework, particularly T1078 Valid Accounts for credential theft via interception and T1557 Adversary-in-the-Middle for active manipulation of network traffic during a session. The ability to inject messages poses a significant risk to industrial control systems or IoT deployments that rely on Eclipse Ditto for device management, as attackers could send false telemetry data or issue unauthorized commands to connected devices. While the Java client, browser/DOM JavaScript client, and HTTP transport of the Node.js client remain unaffected due to their distinct implementation paths, organizations using the vulnerable Node.js WebSocket-based clients are exposed to significant risk until remediation is applied.
To mitigate this vulnerability, immediate action is required for all systems utilizing the affected versions of the Eclipse Ditto Node.js JavaScript client libraries. The primary recommendation is to upgrade to a version of @eclipse-ditto/ditto-javascript-client-node that includes proper certificate validation logic by default or provides a secure configuration mechanism to enforce it. If upgrading is not immediately possible, organizations should consider isolating these clients within network segments where TLS interception is strictly controlled and monitored using dedicated security appliances configured with trusted certificates known to the application environment, although this is a less robust solution than fixing the code itself. Additionally, implementing strict monitoring for anomalous WebSocket traffic patterns can help detect potential exploitation attempts in real-time. Security teams should also review their certificate management practices to ensure that any intermediate proxies or load balancers involved in TLS termination are properly configured and monitored, as they become critical points of trust when client-side validation is absent.