CVE-2021-22328
📋 TL;DR
A denial-of-service vulnerability in specific Huawei CloudEngine switches allows attackers to craft malicious packets that cause service disruption. Affected systems include CloudEngine 12800, 5800, 6800, and 7800 series switches running V200R005C00SPC800 firmware. Successful exploitation can lead to abnormal service behavior and potential downtime.
💻 Affected Systems
- CloudEngine 12800
- CloudEngine 5800
- CloudEngine 6800
- CloudEngine 7800
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete service disruption affecting network connectivity and dependent services, potentially causing extended downtime until systems are restored.
Likely Case
Partial service degradation affecting specific switch functions, leading to intermittent connectivity issues and performance problems.
If Mitigated
Minimal impact with proper network segmentation, rate limiting, and monitoring in place to detect and block malicious packets.
🎯 Exploit Status
Exploitation requires crafting specific packets but does not require authentication. No public exploit code has been disclosed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Update to versions beyond V200R005C00SPC800
Vendor Advisory: https://www.huawei.com/en/psirt/security-advisories/huawei-sa-20210407-01-dos-en
Restart Required: Yes
Instructions:
1. Download updated firmware from Huawei support portal. 2. Backup current configuration. 3. Upload and install new firmware. 4. Reboot switch. 5. Verify firmware version and functionality.
🔧 Temporary Workarounds
Network Segmentation
allIsolate affected switches from untrusted networks and implement strict access controls.
Rate Limiting
linuxImplement packet rate limiting on switch interfaces to mitigate DoS attempts.
qos car inbound any cir 1000 cbs 150000
🧯 If You Can't Patch
- Implement strict network segmentation to isolate vulnerable switches
- Deploy intrusion prevention systems to detect and block malicious packets
🔍 How to Verify
Check if Vulnerable:
Check firmware version using 'display version' command and verify if it matches V200R005C00SPC800Check Version:
display version | include V200R005C00SPC800Verify Fix Applied:
After patching, run 'display version' to confirm firmware version has been updated beyond V200R005C00SPC800📡 Detection & Monitoring
Log Indicators:
- Unusual packet drops
- Service restart logs
- High CPU/memory utilization alerts
Network Indicators:
- Abnormal packet patterns targeting switch management interfaces
- Sudden increase in malformed packets
SIEM Query:
source="huawei-switch" AND ("service abnormal" OR "packet drop" OR "CPU high")