CVE-2019-9871
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code with root privileges on Jector Smart TV FM-K75 devices. The device exposes an Android Debug Bridge (adb) port with root permissions, enabling complete system compromise. Only users of Jector Smart TV FM-K75 devices are affected.
💻 Affected Systems
- Jector Smart TV FM-K75
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device takeover with root access, allowing installation of malware, data theft, device bricking, or use as a botnet node.
Likely Case
Remote attackers gaining full control of the TV, potentially accessing connected devices, stealing credentials, or modifying system settings.
If Mitigated
No impact if the adb port is properly secured or disabled, or if network access is restricted.
🎯 Exploit Status
Standard adb commands can be used for exploitation; no special tools required.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: No
Instructions:
No official patch available from vendor. Users must implement workarounds.
🔧 Temporary Workarounds
Disable adb port
allDisable the Android Debug Bridge port to prevent remote access
adb shell settings put global adb_enabled 0
adb shell setprop service.adb.tcp.port -1
Block adb port with firewall
linuxBlock port 5555 (default adb port) at network level
iptables -A INPUT -p tcp --dport 5555 -j DROP
🧯 If You Can't Patch
- Isolate TV on separate VLAN with no internet access
- Implement network segmentation to restrict access to TV from trusted networks only
🔍 How to Verify
Check if Vulnerable:
Scan device for open port 5555 using nmap: nmap -p 5555 <TV_IP>Check Version:
No specific version check; all FM-K75 models are vulnerableVerify Fix Applied:
Verify port 5555 is closed: nmap -p 5555 <TV_IP> should show filtered/closed📡 Detection & Monitoring
Log Indicators:
- Unexpected adb connections in system logs
- Root shell access from unknown sources
Network Indicators:
- Port 5555 open on TV devices
- Unexpected adb protocol traffic
SIEM Query:
destination_port=5555 AND (protocol="adb" OR application="Android Debug Bridge")