CVE-2022-21217
📋 TL;DR
CVE-2022-21217 is a critical out-of-bounds write vulnerability in Reolink RLC-410W IP cameras that allows remote attackers to execute arbitrary code by sending specially crafted HTTP requests to the TestEmail functionality. This affects organizations and individuals using vulnerable Reolink camera models exposed to network access. Successful exploitation could lead to complete device compromise.
💻 Affected Systems
- Reolink RLC-410W
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to full device takeover, lateral movement to other network devices, persistent backdoor installation, and potential data exfiltration.
Likely Case
Remote code execution allowing attacker to disable camera functionality, modify video feeds, or use device as pivot point for further attacks.
If Mitigated
Limited impact if device is isolated in separate VLAN with strict network segmentation and access controls.
🎯 Exploit Status
Exploitation requires sending crafted HTTP requests to the vulnerable endpoint; detailed technical analysis available in Talos reports.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Reolink firmware updates for versions after v3.0.0.136_20121102
Vendor Advisory: https://support.reolink.com/hc/en-us/articles/360061010111
Restart Required: Yes
Instructions:
1. Log into Reolink camera web interface. 2. Navigate to Settings > System > Maintenance. 3. Check for firmware updates. 4. Download and install latest firmware. 5. Reboot camera after update.
🔧 Temporary Workarounds
Disable TestEmail functionality
allRemove or disable the TestEmail feature if not required
Network segmentation
allIsolate cameras in separate VLAN with strict firewall rules
🧯 If You Can't Patch
- Segment cameras into isolated network with no internet access
- Implement strict firewall rules blocking all inbound HTTP traffic to camera management interfaces
🔍 How to Verify
Check if Vulnerable:
Check firmware version in camera web interface: Settings > System > Device InformationCheck Version:
curl -s http://[CAMERA_IP]/cgi-bin/api.cgi?cmd=GetDevInfo | grep FirmwareVerify Fix Applied:
Verify firmware version is updated beyond v3.0.0.136_20121102 and test TestEmail functionality📡 Detection & Monitoring
Log Indicators:
- Unusual HTTP POST requests to /cgi-bin/api.cgi with TestEmail parameters
- Multiple failed TestEmail attempts
Network Indicators:
- HTTP requests to camera IP with crafted TestEmail payloads
- Unusual outbound connections from camera after exploitation
SIEM Query:
source="camera_logs" AND (uri_path="/cgi-bin/api.cgi" AND query="TestEmail")