CVE-2021-26571
📋 TL;DR
A buffer overflow vulnerability in the Baseboard Management Controller firmware of HPE Apollo 70 Systems allows local attackers to execute arbitrary code. This affects systems running BMC firmware versions prior to 3.0.14.0. Attackers with local access to the BMC interface could potentially gain elevated privileges.
💻 Affected Systems
- HPE Apollo 70 System
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of the BMC, allowing persistent access, firmware modification, and potential lateral movement to the host system.
Likely Case
Local privilege escalation on the BMC, enabling unauthorized access to management functions and system monitoring data.
If Mitigated
Limited impact due to network segmentation and restricted BMC access, with attackers unable to reach the vulnerable interface.
🎯 Exploit Status
Requires local access to the BMC interface; buffer overflow in libifc.so webgetactivexcfg function.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 3.0.14.0
Vendor Advisory: https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf04080en_us
Restart Required: Yes
Instructions:
1. Download firmware version 3.0.14.0 from HPE support portal. 2. Access BMC web interface. 3. Navigate to firmware update section. 4. Upload and apply the update. 5. Reboot the system to complete installation.
🔧 Temporary Workarounds
Restrict BMC Network Access
allLimit access to BMC management interface to trusted networks only.
Configure firewall rules to restrict access to BMC IP/ports
Disable Unused BMC Services
allDisable web interface if not required for management.
Use BMC CLI or web interface to disable web services
🧯 If You Can't Patch
- Isolate BMC management network from production networks
- Implement strict access controls and authentication for BMC interfaces
🔍 How to Verify
Check if Vulnerable:
Check BMC firmware version via web interface or SSH: show versionCheck Version:
ssh admin@bmc_ip show versionVerify Fix Applied:
Verify firmware version is 3.0.14.0 or later📡 Detection & Monitoring
Log Indicators:
- Unusual BMC authentication attempts
- Multiple failed web interface connections
- BMC process crashes
Network Indicators:
- Unusual traffic to BMC web ports (typically 80/443)
- Multiple connection attempts to /cgi-bin/webgetactivexcfg
SIEM Query:
source="bmc_logs" AND (event="authentication_failure" OR event="process_crash")