Trilium Notes Authentication Bypass Vulnerability in Clipper API for Electron Desktop Builds

A vulnerability allowing full authentication bypass in the Clipper API of Trilium Notes Desktop has been identified. This issue affects versions through 0.102.1, with the Clipper API in Trilium Desktop version 0.101.3 being particularly vulnerable. When running in an Electron environment, the application disables authentication middleware for the Clipper API, leaving endpoints like '/api/clipper/notes' exposed to the network without any password, API token, or CSRF protection. This vulnerability allows an attacker on a shared network to access unauthorized data, inject malicious content into a user's private database, and potentially compromise the local system.

Impact

Exploitation of this vulnerability bypasses the entire security model of Trilium, allowing unauthorized data manipulation and serving as a primary delivery vector for remote code execution. It assumes that local network access is equivalent to authenticated access, which is a dangerous fallacy in modern network environments.

Reproduction

To reproduce this vulnerability, first ensure that Trilium Notes Desktop is running in an Electron environment. Once the application is open, an attacker can scan the local network for open high-range ports using a tool like nmap. After identifying a port where Trilium is running, an unauthenticated request can be sent to the Clipper handshake endpoint to confirm the presence of a vulnerable Trilium instance. Once confirmed, the attacker can inject malicious notes into the user's workspace, exploiting the authentication bypass.

Remediation

Users are advised to update Trilium Notes to version 0.102.2 or later, where this vulnerability has been fixed.