CVE-2025-64683: JetBrains Hub Information Disclosure

CVE-2025-64683 Overview

A significant information disclosure vulnerability has been identified in JetBrains Hub, the integrated identity management and project collaboration platform used by development teams worldwide. This vulnerability exists in the Users API and allows unauthorized access to sensitive user information without requiring authentication or user interaction.

Critical Impact

Unauthorized attackers can remotely access sensitive user data through the Users API, potentially exposing confidential information including user credentials, profile details, and organizational data managed by JetBrains Hub.

Affected Products

• JetBrains Hub versions prior to 2025.3.104432

Discovery Timeline

• 2025-11-10 - CVE CVE-2025-64683 published to NVD
• 2025-11-21 - Last updated in NVD database

Technical Details for CVE-2025-64683

Vulnerability Analysis

This information disclosure vulnerability in JetBrains Hub stems from improper access controls in the Users API endpoint. The flaw allows unauthenticated remote attackers to query and retrieve sensitive user information that should be restricted to authorized personnel only.

The vulnerability is particularly concerning because it can be exploited over the network without any prerequisites. An attacker does not need valid credentials, special privileges, or any form of user interaction to successfully exploit this weakness. The confidentiality impact is significant, as attackers can potentially access the full scope of user data managed by the Hub platform.

JetBrains Hub serves as a central authentication and authorization hub for JetBrains products like YouTrack, TeamCity, and Upsource, making this vulnerability potentially impactful across an organization's entire development infrastructure.

Root Cause

The root cause of CVE-2025-64683 is related to CWE-362 (Race Condition), suggesting that improper synchronization in the Users API allows concurrent requests to bypass authorization checks. This race condition enables attackers to access user information during a brief window when access control validations are incomplete or inconsistent.

Attack Vector

The attack vector is network-based, requiring no authentication or user interaction. An attacker can craft malicious API requests targeting the vulnerable Users API endpoint in JetBrains Hub. The low attack complexity means that exploitation requires minimal technical sophistication—standard HTTP requests to the API endpoint may be sufficient to extract sensitive user information.

The vulnerability allows for high confidentiality impact while maintaining no impact on integrity or availability, indicating this is purely an information extraction vulnerability. Attackers can silently gather user data without modifying systems or disrupting services.

Detection Methods for CVE-2025-64683

Indicators of Compromise

• Unusual or excessive API requests to the Users API endpoint from unknown or external IP addresses
• Anomalous access patterns showing bulk retrieval of user data from the Hub Users API
• API authentication logs showing successful data retrieval without corresponding valid authentication tokens
• Unexpected spikes in outbound network traffic from Hub servers containing user data

Detection Strategies

• Implement API request monitoring to identify unusual query patterns or volumes targeting the Users API
• Deploy network intrusion detection rules to flag unauthorized access attempts to JetBrains Hub endpoints
• Enable detailed API access logging and audit trails for all Users API interactions
• Configure SIEM alerts for any unauthenticated access attempts to protected API resources

Monitoring Recommendations

• Continuously monitor JetBrains Hub access logs for signs of reconnaissance or data exfiltration
• Establish baseline metrics for normal Users API usage patterns to detect anomalies
• Review authentication failures and suspicious session activities on a regular basis
• Implement real-time alerting for any access to the Users API from untrusted network segments

How to Mitigate CVE-2025-64683

Immediate Actions Required

• Upgrade JetBrains Hub to version 2025.3.104432 or later immediately
• Restrict network access to the JetBrains Hub Users API to trusted internal networks only
• Review access logs to identify any potential prior exploitation of this vulnerability
• Implement additional API rate limiting and authentication requirements as a defense-in-depth measure

Patch Information

JetBrains has addressed this vulnerability in JetBrains Hub version 2025.3.104432. Organizations should apply this update as soon as possible to remediate the information disclosure risk. The security patch is available through the standard JetBrains update channels. For detailed information on security fixes, refer to the JetBrains Security Issues Fixed advisory page.

Workarounds

• Place JetBrains Hub behind a reverse proxy with strict access controls until patching is complete
• Implement network segmentation to limit exposure of the Hub API to only necessary internal services
• Apply IP-based allowlisting to restrict Users API access to known and trusted administrative hosts
• Enable Web Application Firewall (WAF) rules to detect and block suspicious API query patterns

# Example: Restrict access to Hub API via nginx reverse proxy
location /api/rest/users {
    allow 10.0.0.0/8;      # Allow internal network
    allow 192.168.1.0/24;  # Allow admin network
    deny all;              # Deny all other access
    
    proxy_pass http://hub-backend:8080;
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
}