CVE-2023-3656
📋 TL;DR
CVE-2023-3656 is an unauthenticated remote code execution vulnerability in cashIT! devices from PoS/Dienstleistung, Entwicklung & Vertrieb GmbH. Attackers can exploit this via an exposed HTTP endpoint to execute arbitrary code without authentication. All devices running versions up to 03.A06rks 2023.02.37 are affected.
💻 Affected Systems
- cashIT! devices from PoS/Dienstleistung, Entwicklung & Vertrieb GmbH
📦 What is this software?
Cashit\! by Cashit
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise allowing attackers to install malware, steal sensitive payment data, disrupt operations, and pivot to other network systems.
Likely Case
Attackers install ransomware or cryptocurrency miners, steal payment card data, and disrupt point-of-sale operations.
If Mitigated
Limited impact with proper network segmentation and monitoring, though systems remain vulnerable to exploitation.
🎯 Exploit Status
The vulnerability requires no authentication and is triggered via HTTP, making exploitation straightforward for attackers with network access.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions after 03.A06rks 2023.02.37
Vendor Advisory: https://www.cashit.at/
Restart Required: Yes
Instructions:
1. Contact cashIT! vendor for updated firmware. 2. Backup device configuration. 3. Apply firmware update. 4. Restart device. 5. Verify update was successful.
🔧 Temporary Workarounds
Network Segmentation
allIsolate cashIT! devices from untrusted networks and restrict access to necessary IPs only.
Firewall Rules
allBlock external access to cashIT! HTTP endpoints and restrict internal access to authorized systems only.
🧯 If You Can't Patch
- Implement strict network segmentation to isolate cashIT! devices from other systems
- Deploy intrusion detection systems to monitor for exploitation attempts and anomalous traffic
🔍 How to Verify
Check if Vulnerable:
Check device firmware version via device management interface or console. If version is 03.A06rks 2023.02.37 or earlier, device is vulnerable.Check Version:
Check via device web interface or console - specific command varies by device modelVerify Fix Applied:
Verify firmware version is newer than 03.A06rks 2023.02.37 and test that HTTP endpoints no longer accept malicious payloads.📡 Detection & Monitoring
Log Indicators:
- Unusual HTTP requests to cashIT! endpoints
- Unexpected process execution
- System configuration changes
Network Indicators:
- HTTP requests with suspicious payloads to cashIT! devices
- Outbound connections from cashIT! devices to unknown IPs
SIEM Query:
source_ip="cashIT_device" AND (http_method="POST" OR http_method="GET") AND (url_contains("/vulnerable_endpoint") OR http_user_agent="malicious")