Eclipse Ditto: Improper Certificate Validation
CVE-2026-84197 is a critical-severity improper certificate validation vulnerability in Eclipse Ditto from Eclipse Foundation, with a CVSS 4.0 base score of 9.2 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 3.8.1, 3.9.1 as the first without the flaw, so updating Eclipse Ditto to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.34% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update Eclipse Ditto to 3.8.1 or 3.9.1, whichever matches your release line, or a later version.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Eclipse Foundation | Eclipse Ditto | 2.0.0 up to, but not including, 3.8.1; 3.9.0 up to, but not including, 3.9.1; 1.0.0 through 2.1.0 | 3.8.1, 3.9.1 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Attack requirements
- PresentThe target must be in a specific state or configuration for the attack to work.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Confidentiality (vulnerable system)
- HighSerious loss of confidentiality on the vulnerable system.
- Integrity (vulnerable system)
- HighSerious loss of integrity on the vulnerable system.
- Availability (vulnerable system)
- LowLimited loss of availability on the vulnerable system.
- Confidentiality (other systems)
- NoneNo loss of confidentiality on systems beyond the vulnerable one.
- Integrity (other systems)
- NoneNo loss of integrity on systems beyond the vulnerable one.
- Availability (other systems)
- NoneNo loss of availability on systems beyond the vulnerable one.
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. Scored by CNA (eclipse.org).
Official description
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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Certificate Validation
The product does not validate, or incorrectly validates, a certificate.
How developers prevent this class of flaw
- Certificates should be carefully managed and checked to assure that data are encrypted with the intended owner's public key.
- If certificate pinning is being used, ensure that all relevant properties of the certificate are fully validated before the certificate is pinned, including the hostname.
More Improper Certificate Validation vulnerabilities (CWE-295)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other vulnerabilities in Eclipse Ditto
- 7.6 High severity
Recent Improper Certificate Validation vulnerabilities
- 9.9 Critical severity
- 7.6 High severity
- 7.3 High severity
- 7.4 High severity
- 9.1 Critical severity
- 7.5 High severity
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