CVE-2021-43183
📋 TL;DR
This vulnerability allows attackers to bypass authentication throttling mechanisms in JetBrains Hub, potentially enabling brute-force attacks on login credentials. All organizations running vulnerable versions of JetBrains Hub are affected.
💻 Affected Systems
- JetBrains Hub
📦 What is this software?
Hub by Jetbrains
⚠️ Risk & Real-World Impact
Worst Case
Attackers could perform unlimited authentication attempts, leading to account takeover, credential stuffing attacks, and potential full system compromise.
Likely Case
Attackers bypass rate limiting to perform credential brute-forcing against user accounts, potentially compromising individual accounts.
If Mitigated
With proper network segmentation and monitoring, impact is limited to authentication attempts that can be detected and blocked.
🎯 Exploit Status
Authentication bypass vulnerabilities typically have low exploitation complexity once the bypass method is understood.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2021.1.13690 and later
Vendor Advisory: https://blog.jetbrains.com/blog/2021/11/08/jetbrains-security-bulletin-q3-2021/
Restart Required: Yes
Instructions:
1. Backup your Hub instance. 2. Download and install Hub version 2021.1.13690 or later from JetBrains. 3. Follow the upgrade instructions in the Hub documentation. 4. Restart the Hub service.
🔧 Temporary Workarounds
Network-based rate limiting
allImplement network-level rate limiting using WAF or load balancer to restrict authentication attempts
IP-based blocking
allConfigure firewall rules to block IPs with excessive failed authentication attempts
🧯 If You Can't Patch
- Implement strong password policies and multi-factor authentication
- Monitor authentication logs for unusual patterns and implement alerting
🔍 How to Verify
Check if Vulnerable:
Check Hub version in administration interface or via API. If version is below 2021.1.13690, system is vulnerable.Check Version:
Check Hub web interface under Administration → System Information or use Hub REST API endpoint /api/rest/system/infoVerify Fix Applied:
Verify Hub version is 2021.1.13690 or later and test authentication throttling functionality.📡 Detection & Monitoring
Log Indicators:
- Multiple failed authentication attempts from same source without throttling
- Unusual authentication patterns bypassing rate limits
Network Indicators:
- High volume of authentication requests to Hub endpoints
- Authentication traffic patterns inconsistent with normal user behavior
SIEM Query:
source="hub" AND (event_type="authentication_failure" AND count > threshold) OR (authentication_rate > expected_limit)