CVE-2023-31435
📋 TL;DR
This vulnerability in evasys software allows authenticated attackers to bypass authorization controls and access unauthorized data through direct function calls. It affects evasys versions before 8.2 Build 2286 and 9.x before 9.0 Build 2401. Attackers can read and write data they shouldn't have access to.
💻 Affected Systems
- evasys
📦 What is this software?
Evasys by Evasys
Evasys by Evasys
⚠️ Risk & Real-World Impact
Worst Case
Attackers could access sensitive student data, modify survey results, tamper with templates, and potentially compromise the entire evasys system integrity.
Likely Case
Unauthorized access to survey data, questionnaire responses, and administrative functions leading to data leakage and manipulation.
If Mitigated
Limited impact if proper network segmentation, strong authentication, and least privilege principles are implemented.
🎯 Exploit Status
Exploitation requires authenticated access but direct function calls bypass authorization checks.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 8.2 Build 2286 or 9.0 Build 2401
Vendor Advisory: https://cves.at/posts/cve-2023-31435/writeup/
Restart Required: Yes
Instructions:
1. Download latest evasys version from vendor. 2. Backup current installation. 3. Apply patch/upgrade to 8.2 Build 2286 or 9.0 Build 2401. 4. Restart evasys services. 5. Verify functionality.
🔧 Temporary Workarounds
Network Segmentation
allRestrict access to evasys to only trusted networks and users
Enhanced Authentication
allImplement multi-factor authentication and strong password policies
🧯 If You Can't Patch
- Implement strict network access controls and firewall rules
- Enable detailed logging and monitoring for unauthorized access attempts
🔍 How to Verify
Check if Vulnerable:
Check evasys version in administration interface or configuration filesCheck Version:
Check evasys web interface admin panel or consult system documentationVerify Fix Applied:
Verify version is 8.2 Build 2286 or higher for 8.x, or 9.0 Build 2401 or higher for 9.x📡 Detection & Monitoring
Log Indicators:
- Unauthorized access attempts to sensitive functions
- Unusual data access patterns from authenticated users
Network Indicators:
- Direct function calls bypassing normal UI flows
- Unusual API requests
SIEM Query:
source="evasys" AND (event_type="unauthorized_access" OR user_privilege_escalation=true)