Overview
This report discusses a critical vulnerability, CVE-2025-53544, found in Trilium Notes, an open-source, cross-platform note taking application. This vulnerability allows unauthenticated attackers to bypass the brute-force protection in the initial sync seed retrieval endpoint, potentially leading to system compromise or data leakage.
Vulnerability Summary
CVE ID: CVE-2025-53544
Severity: High (CVSS Score: 7.5)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise or data leakage
Affected Products
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Product | Affected Versions
Trilium Notes | Versions below 0.97.0
How the Exploit Works
An unauthenticated attacker can exploit this vulnerability by repeatedly guessing the login password for Trilium Notes. As the application does not require a username and has insufficient brute-force protection in place, this allows the attacker to avoid triggering rate limiting, thus making the brute force attack more feasible. Successful exploitation could result in unauthorized access, system compromise, or data leakage.
Conceptual Example Code
The conceptual example below demonstrates how an attacker might exploit this vulnerability:
POST /sync-seed-retrieval HTTP/1.1
Host: target.example.com
Content-Type: application/json
{ "password_guess": "..." }In this example, the attacker sends repeated HTTP POST requests to the “/sync-seed-retrieval” endpoint, each time guessing a different password in the “password_guess” field. The lack of rate limiting means the attacker can make unlimited guesses without being blocked or slowed down.
Remediation
The vendor has fixed this issue in Trilium Notes version 0.97.0. Users of affected versions are advised to upgrade as soon as possible. Alternatively, users can apply a WAF/IDS as a temporary mitigation measure until the patch can be applied.
