CVE-2024-52598
📋 TL;DR
CVE-2024-52598 is a Server-Side Request Forgery (SSRF) vulnerability in 2FAuth version 5.4.1 that allows attackers to make the application send HTTP requests to arbitrary internal or external URLs. Combined with a URI validation bypass, attackers can retrieve text-based content from systems accessible to the web server. All users running 2FAuth version 5.4.1 or earlier are affected.
💻 Affected Systems
- 2FAuth
📦 What is this software?
2fauth by 2fauth
⚠️ Risk & Real-World Impact
Worst Case
Attackers could access internal services, retrieve sensitive data from cloud metadata services, or perform port scanning of internal networks through the vulnerable application.
Likely Case
Information disclosure from internal services, potential access to cloud instance metadata, and reconnaissance of internal network resources.
If Mitigated
Limited impact if network segmentation restricts the application's access to sensitive internal resources and external internet access is controlled.
🎯 Exploit Status
Exploitation requires authenticated access to the API endpoint. The advisory includes technical details that make exploitation straightforward.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 5.4.1 (the advisory indicates this version fixes the issue)
Vendor Advisory: https://github.com/Bubka/2FAuth/security/advisories/GHSA-xwxc-w7v3-2p4j
Restart Required: Yes
Instructions:
1. Update 2FAuth to version 5.4.1 or later. 2. Restart the application. 3. Verify the fix by testing the vulnerable endpoint.
🔧 Temporary Workarounds
Disable API endpoint
allTemporarily disable or restrict access to the vulnerable /api/v1/twofaccounts/preview endpoint
# Configure web server (nginx example) to block the endpoint
location /api/v1/twofaccounts/preview { deny all; }
Network restrictions
linuxImplement network controls to restrict outbound HTTP requests from the application server
# Use firewall rules to restrict outbound traffic
iptables -A OUTPUT -p tcp --dport 80 -j DROP
iptables -A OUTPUT -p tcp --dport 443 -j DROP
🧯 If You Can't Patch
- Implement strict network segmentation to limit the application's access to internal resources
- Deploy a web application firewall (WAF) with SSRF protection rules
🔍 How to Verify
Check if Vulnerable:
Check if the application version is 5.4.1 or earlier. Test the API endpoint POST /api/v1/twofaccounts/preview with a malicious payload containing a URL with #.svg appended.Check Version:
Check the application's version in the web interface or configuration files. For Docker: docker inspect 2fauth_container | grep -i versionVerify Fix Applied:
After updating, test the same endpoint with malicious payloads to confirm they are rejected. Verify the application version is 5.4.1 or later.📡 Detection & Monitoring
Log Indicators:
- Unusual outbound HTTP requests from the application server
- Requests to /api/v1/twofaccounts/preview with unusual URLs
- Failed image retrieval attempts with appended #.svg
Network Indicators:
- HTTP requests from the application server to internal IP ranges or unusual domains
- Outbound requests on non-standard ports from the web application
SIEM Query:
source="web_server_logs" AND (uri="/api/v1/twofaccounts/preview" AND (url="*#.svg" OR user_agent="*curl*" OR status_code=500))