Eclipse Ditto Node.js Client WS Cert Validation Bypass 2.0.0-3.9.0
CVE-2026-84197 Published on September 8, 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.

NVD

Vulnerability Analysis

CVE-2026-84197 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity and availability.

Attack Vector:
NETWORK
Attack Complexity:
LOW
Privileges Required:
NONE
User Interaction:
NONE

Weakness Types

Improper Certificate Validation

The software does not validate, or incorrectly validates, a certificate. When a certificate is invalid or malicious, it might allow an attacker to spoof a trusted entity by interfering in the communication path between the host and client. The software might connect to a malicious host while believing it is a trusted host, or the software might be deceived into accepting spoofed data that appears to originate from a trusted host.

Improper Validation of Certificate with Host Mismatch

The software communicates with a host that provides a certificate, but the software does not properly ensure that the certificate is actually associated with that host.

What is a Man-in-the-Middle / MITM Vulnerability?

The product does not adequately verify the identity of actors at both ends of a communication channel, or does not adequately ensure the integrity of the channel, in a way that allows the channel to be accessed or influenced by an actor that is not an endpoint. In order to establish secure communication between two parties, it is often important to adequately verify the identity of entities at each end of the communication channel. Inadequate or inconsistent verification may result in insufficient or incorrect identification of either communicating entity. This can have negative consequences such as misplaced trust in the entity at the other end of the channel. An attacker can leverage this by interposing between the communicating entities and masquerading as the original entity. In the absence of sufficient verification of identity, such an attacker can eavesdrop and potentially modify the communication between the original entities.

CVE-2026-84197 has been classified to as a Man-in-the-Middle / MITM vulnerability or weakness.


Affected Versions

Eclipse Foundation Eclipse Ditto: Eclipse Foundation Eclipse Ditto: