CVE-2022-35729
📋 TL;DR
An out-of-bounds read vulnerability in OpenBMC firmware for certain Intel platforms allows unauthenticated attackers to potentially cause denial of service via network access. This affects systems running vulnerable versions of OpenBMC firmware on Intel server platforms. The vulnerability could disrupt baseboard management controller functionality.
💻 Affected Systems
- Intel server platforms with OpenBMC firmware
📦 What is this software?
Openbmc by Openbmc Project
⚠️ Risk & Real-World Impact
Worst Case
Complete disruption of BMC functionality, preventing remote management, monitoring, and potentially affecting host system stability.
Likely Case
Temporary denial of service affecting BMC web interface, IPMI, or Redfish API services until BMC reset.
If Mitigated
Minimal impact with proper network segmentation and access controls limiting BMC exposure.
🎯 Exploit Status
Requires network access to BMC management interface but no authentication. Specific exploit details not publicly documented.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: OpenBMC version 0.72 or later
Vendor Advisory: http://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00737.html
Restart Required: Yes
Instructions:
1. Download OpenBMC firmware version 0.72 or later from Intel. 2. Follow Intel's BMC firmware update procedures for your specific platform. 3. Apply firmware update through BMC web interface or IPMI. 4. Reboot BMC after update completes.
🔧 Temporary Workarounds
Network segmentation
allIsolate BMC management interfaces from untrusted networks
Access control lists
linuxRestrict network access to BMC interfaces using firewall rules
iptables -A INPUT -p tcp --dport 443 -s trusted_network -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP
🧯 If You Can't Patch
- Implement strict network segmentation to isolate BMC interfaces
- Monitor BMC logs for unusual activity and implement rate limiting
🔍 How to Verify
Check if Vulnerable:
Check OpenBMC firmware version via BMC web interface or IPMI: 'ipmitool mc info' may show firmware versionCheck Version:
ipmitool mc info | grep 'Firmware Revision' or check BMC web interfaceVerify Fix Applied:
Confirm OpenBMC version is 0.72 or higher through BMC interface📡 Detection & Monitoring
Log Indicators:
- BMC crash logs
- Unexpected BMC reboots
- Failed authentication attempts to BMC
Network Indicators:
- Unusual traffic patterns to BMC ports (80, 443, 623)
- Multiple connection attempts to BMC
SIEM Query:
source="bmc_logs" AND ("crash" OR "restart" OR "panic") OR dest_port IN (80, 443, 623) AND src_ip NOT IN trusted_networks