CVE-2021-29101
📋 TL;DR
This vulnerability allows unauthenticated remote attackers to read arbitrary files on ArcGIS GeoEvent Server systems by exploiting a directory traversal flaw in read-only operations. It affects all versions up to and including 10.8.1. Attackers can access sensitive system files without needing valid credentials.
💻 Affected Systems
- ArcGIS GeoEvent Server
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attackers exfiltrate sensitive configuration files, credentials, or system data leading to full system compromise or lateral movement.
Likely Case
Unauthorized access to internal files, potentially exposing server configurations, logs, or other sensitive information.
If Mitigated
Limited to reading files accessible to the GeoEvent Server process, but still exposes potentially sensitive data.
🎯 Exploit Status
Directory traversal vulnerabilities are typically easy to exploit with basic HTTP requests.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Apply Security Update 2021 Patch 1
Vendor Advisory: https://www.esri.com/arcgis-blog/products/ext-server-geoevent/administration/arcgis-geoevent-server-security-update-2021-patch-1
Restart Required: Yes
Instructions:
1. Download Security Update 2021 Patch 1 from My Esri. 2. Stop GeoEvent Server services. 3. Apply the patch. 4. Restart GeoEvent Server services. 5. Verify the update was successful.
🔧 Temporary Workarounds
Network Segmentation
allRestrict access to GeoEvent Server to trusted networks only
Web Application Firewall
allConfigure WAF rules to block directory traversal patterns
🧯 If You Can't Patch
- Implement strict network access controls to limit exposure
- Monitor for unusual file access patterns in server logs
🔍 How to Verify
Check if Vulnerable:
Check GeoEvent Server version. If version is 10.8.1 or earlier, system is vulnerable.Check Version:
Check version in GeoEvent Server Manager interface or installation directoryVerify Fix Applied:
Verify GeoEvent Server version shows Security Update 2021 Patch 1 applied📡 Detection & Monitoring
Log Indicators:
- Unusual file path patterns in web server logs
- Multiple failed attempts to access system files
Network Indicators:
- HTTP requests containing '../' patterns to GeoEvent Server endpoints
SIEM Query:
source="geoevent_logs" AND (uri="*../*" OR uri="*..\\*")