CVE-2021-22449
📋 TL;DR
CVE-2021-22449 is a logic vulnerability in Huawei Elf-G10HN devices that allows unauthenticated attackers to add users as friends without consent. This affects Huawei Elf-G10HN smart home gateways running version 1.0.0.608. The vulnerability enables unauthorized social connections within the device's ecosystem.
💻 Affected Systems
- Huawei Elf-G10HN
📦 What is this software?
Elf G10hn by Huawei
⚠️ Risk & Real-World Impact
Worst Case
Attackers could establish persistent access through friend connections, potentially enabling further social engineering attacks, privacy violations, or preparation for more sophisticated attacks within the smart home network.
Likely Case
Unauthorized users being added to friend lists without consent, potentially enabling monitoring of device activities or preparation for social engineering attacks.
If Mitigated
Limited impact with proper network segmentation and access controls, though the core vulnerability remains present in affected devices.
🎯 Exploit Status
The advisory mentions 'specific operations' are required but doesn't detail them. Being unauthenticated with low complexity suggests straightforward exploitation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Not specified in advisory, but Huawei recommends updating to latest version
Vendor Advisory: https://www.huawei.com/en/psirt/security-advisories/huawei-sa-20210630-01-logic-en
Restart Required: Yes
Instructions:
1. Log into Huawei device management interface. 2. Check for firmware updates. 3. Apply available updates. 4. Reboot device after update completes.
🔧 Temporary Workarounds
Network Isolation
allIsolate the Elf-G10HN device from untrusted networks to prevent external exploitation
Access Control
allImplement strict firewall rules to limit access to device management interfaces
🧯 If You Can't Patch
- Segment the device on a dedicated VLAN with strict access controls
- Monitor network traffic to/from the device for suspicious friend addition attempts
🔍 How to Verify
Check if Vulnerable:
Check device firmware version through web interface or management console. If version is 1.0.0.608, device is vulnerable.Check Version:
Check via device web interface or refer to device documentation for CLI commandsVerify Fix Applied:
Verify firmware version has been updated from 1.0.0.608 to a newer version through device management interface.📡 Detection & Monitoring
Log Indicators:
- Unexpected friend addition events
- Authentication bypass attempts in logs
- Unusual connection patterns to device management interfaces
Network Indicators:
- Unusual HTTP/HTTPS requests to device management ports
- Traffic patterns indicating friend addition operations
SIEM Query:
source="huawei-elf-g10hn" AND (event_type="friend_add" OR auth_result="bypass")