CVE-2021-37425
📋 TL;DR
CVE-2021-37425 is an XML External Entity (XXE) vulnerability in Altova MobileTogether Server that allows attackers to read sensitive files, including configuration files, certificates, and private keys. It affects MobileTogether Server versions before 7.3 SP1. Attackers can exploit this via specific endpoints like /workflowmanagement.
💻 Affected Systems
- Altova MobileTogether Server
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through certificate/private key theft leading to impersonation, data exfiltration, and lateral movement.
Likely Case
Sensitive configuration file and credential theft enabling further attacks against the server and connected systems.
If Mitigated
Limited impact with proper network segmentation and file permission restrictions.
🎯 Exploit Status
Public exploit details available in disclosure. Simple XXE payloads work against vulnerable endpoints.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 7.3 SP1 and later
Vendor Advisory: https://www.altova.com/mobiletogether
Restart Required: Yes
Instructions:
1. Download MobileTogether Server 7.3 SP1 or later from Altova website. 2. Stop the MobileTogether Server service. 3. Install the updated version. 4. Restart the service.
🔧 Temporary Workarounds
Block Vulnerable Endpoints
allUse web application firewall or reverse proxy to block access to /workflowmanagement and other vulnerable endpoints
# Example nginx location block
location ~ ^/workflowmanagement { deny all; }
# Example Apache .htaccess
RewriteRule ^workflowmanagement - [F]
Restrict File Permissions
allSet strict permissions on mobiletogetherserver.cfg and certificate/private key files
# Linux
chmod 600 mobiletogetherserver.cfg
# Windows
icacls mobiletogetherserver.cfg /inheritance:r /grant:r "Administrators:F"
🧯 If You Can't Patch
- Implement strict network segmentation to isolate MobileTogether Server from sensitive systems
- Deploy web application firewall with XXE protection rules and monitor for exploitation attempts
🔍 How to Verify
Check if Vulnerable:
Check server version via web interface or configuration file. Versions before 7.3 SP1 are vulnerable.Check Version:
# Check version in web interface or config file
cat /path/to/mobiletogetherserver.cfg | grep VersionVerify Fix Applied:
Confirm version is 7.3 SP1 or later and test XXE payloads against /workflowmanagement endpoint return errors.📡 Detection & Monitoring
Log Indicators:
- XML parsing errors with external entity references
- Unusual file access patterns to configuration/certificate files
- Requests to /workflowmanagement with XML payloads
Network Indicators:
- HTTP POST requests to /workflowmanagement containing XXE payloads
- Outbound connections to external domains in XML entities
SIEM Query:
source="mobiletogether.log" AND ("XXE" OR "ENTITY" OR "SYSTEM")🔗 References
- http://seclists.org/fulldisclosure/2021/Aug/12
- https://www.altova.com/mobiletogether
- https://www.redteam-pentesting.de/advisories/rt-sa-2021-002
- https://www.redteam-pentesting.de/en/advisories/-advisories-publicised-vulnerability-analyses
- http://seclists.org/fulldisclosure/2021/Aug/12
- https://www.altova.com/mobiletogether
- https://www.redteam-pentesting.de/advisories/rt-sa-2021-002
- https://www.redteam-pentesting.de/en/advisories/-advisories-publicised-vulnerability-analyses
