CVE-2021-22292
📋 TL;DR
This vulnerability allows remote attackers to cause denial of service (DoS) on affected Huawei eCNS280 devices by sending a large number of specific messages that exhaust system resources. The attack can be performed without authentication, affecting the web application functionality. Only eCNS280 devices running specific vulnerable versions are impacted.
💻 Affected Systems
- Huawei eCNS280
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete unavailability of the web application interface and potential disruption of network services managed by the device, requiring physical intervention to restore functionality.
Likely Case
Web application becomes unresponsive or crashes, preventing administrative access through the web interface while core network functions may continue operating.
If Mitigated
With proper network segmentation and access controls, the attack surface is reduced, limiting potential impact to isolated network segments.
🎯 Exploit Status
Attack requires sending specific messages to trigger resource exhaustion. No authentication is required to exploit.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: V100R005C20 or later
Vendor Advisory: https://www.huawei.com/en/psirt/security-advisories/huawei-sa-20210113-02-dos-en
Restart Required: Yes
Instructions:
1. Download the updated firmware version V100R005C20 or later from Huawei support portal. 2. Backup current configuration. 3. Upload and install the new firmware. 4. Reboot the device. 5. Verify the firmware version after reboot.
🔧 Temporary Workarounds
Network Access Control
allRestrict network access to the device's management interface to trusted IP addresses only
Rate Limiting
allImplement rate limiting on network traffic to the device to prevent flood attacks
🧯 If You Can't Patch
- Isolate the device in a separate network segment with strict access controls
- Implement network monitoring and alerting for unusual traffic patterns to the device
🔍 How to Verify
Check if Vulnerable:
Check the device firmware version via the web interface or CLI. If version is V100R005C00 or V100R005C10, the device is vulnerable.Check Version:
display version (CLI command) or check System Information in web interfaceVerify Fix Applied:
After patching, verify the firmware version shows V100R005C20 or later and test web interface functionality under normal load.📡 Detection & Monitoring
Log Indicators:
- Unusually high number of connection attempts
- System resource exhaustion warnings
- Web service crash/restart events
Network Indicators:
- High volume of specific message types to device management interface
- Sudden increase in traffic to device port
SIEM Query:
source_ip="device_ip" AND (event_type="connection_flood" OR resource_usage>90%)