CVE-2021-42774
📋 TL;DR
A buffer overflow vulnerability in Broadcom Emulex HBA Manager/One Command Manager allows remote unauthenticated attackers to execute arbitrary code when the software is not configured in Strictly Local Management mode. This affects systems using vulnerable versions of the management software with remote firmware download enabled. The vulnerability is particularly dangerous because it requires no authentication in non-secure mode.
💻 Affected Systems
- Broadcom Emulex HBA Manager
- Broadcom Emulex One Command Manager
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data exfiltration, and potential lateral movement within the network.
Likely Case
Remote attackers gaining control of affected systems to install malware, create backdoors, or disrupt storage operations.
If Mitigated
No impact if systems are configured in Strictly Local Management mode or properly patched.
🎯 Exploit Status
Buffer overflow in remote firmware download feature makes exploitation straightforward for skilled attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 11.4.425.0 or 12.8.542.31 and later
Vendor Advisory: https://docs.broadcom.com/doc/elx_HBAManager-Lin-RN12811-101.pdf
Restart Required: Yes
Instructions:
1. Download updated version from Broadcom support portal. 2. Stop HBA Manager service. 3. Install update. 4. Restart service. 5. Verify version.
🔧 Temporary Workarounds
Enable Strictly Local Management Mode
allConfigure HBA Manager to only accept local connections, disabling remote management features.
Configure via HBA Manager GUI or edit configuration files per Broadcom documentation
Network Segmentation
allRestrict network access to HBA Manager ports using firewall rules.
iptables -A INPUT -p tcp --dport [HBA_MANAGER_PORT] -j DROP
netsh advfirewall firewall add rule name="Block HBA Manager" dir=in action=block protocol=TCP localport=[HBA_MANAGER_PORT]
🧯 If You Can't Patch
- Configure in Strictly Local Management mode immediately
- Implement strict network access controls to isolate affected systems
🔍 How to Verify
Check if Vulnerable:
Check HBA Manager version and verify if Strictly Local Management mode is enabled.Check Version:
hba_manager --version or check installed package version via system package managerVerify Fix Applied:
Confirm version is 11.4.425.0 or higher (for 11.x) or 12.8.542.31 or higher (for 12.x).📡 Detection & Monitoring
Log Indicators:
- Unexpected remote connections to HBA Manager service
- Failed firmware download attempts
- Service crashes or abnormal restarts
Network Indicators:
- Unusual traffic to HBA Manager default ports (typically 2301, 2302)
- Malformed packets to firmware download endpoints
SIEM Query:
source="HBA_Manager" AND (event_type="connection" OR event_type="firmware_download") AND src_ip NOT IN [trusted_ips]🔗 References
- https://docs.broadcom.com/doc/elx_HBAManager-Lin-RN12811-101.pdf
- https://www.broadcom.com/products/storage/fibre-channel-host-bus-adapters/emulex-hba-manager
- https://docs.broadcom.com/doc/elx_HBAManager-Lin-RN12811-101.pdf
- https://www.broadcom.com/products/storage/fibre-channel-host-bus-adapters/emulex-hba-manager
