CVE-2021-36347
📋 TL;DR
This CVE describes a stack-based buffer overflow vulnerability in Dell iDRAC9 and iDRAC8 remote management controllers. An authenticated attacker with high privileges could exploit this to execute arbitrary code and gain access to the iDRAC operating system. This affects organizations using vulnerable iDRAC versions for server management.
💻 Affected Systems
- Dell iDRAC9
- Dell iDRAC8
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of iDRAC system leading to persistent access, credential theft, and potential lateral movement to managed servers.
Likely Case
Attacker gains control of iDRAC management interface, enabling server manipulation, data exfiltration, or denial of service.
If Mitigated
Limited impact due to network segmentation and proper access controls preventing exploitation.
🎯 Exploit Status
Requires authentication with high privileges and knowledge of buffer overflow exploitation techniques.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: iDRAC9 5.00.20.00 or later, iDRAC8 2.82.82.82 or later
Vendor Advisory: https://www.dell.com/support/kbdoc/000194038
Restart Required: Yes
Instructions:
1. Download latest iDRAC firmware from Dell Support. 2. Log into iDRAC web interface. 3. Navigate to Maintenance > System Update. 4. Upload and install firmware update. 5. Reboot iDRAC after installation.
🔧 Temporary Workarounds
Restrict iDRAC Network Access
allLimit iDRAC management interface access to trusted networks only.
Implement Strong Authentication Controls
allEnforce multi-factor authentication and strong password policies for iDRAC accounts.
🧯 If You Can't Patch
- Isolate iDRAC interfaces on separate VLAN with strict firewall rules
- Implement network segmentation to prevent lateral movement from compromised iDRAC
🔍 How to Verify
Check if Vulnerable:
Check iDRAC firmware version via web interface or SSH: racadm getversionCheck Version:
racadm getversion | grep -i firmwareVerify Fix Applied:
Confirm firmware version is iDRAC9 >= 5.00.20.00 or iDRAC8 >= 2.82.82.82📡 Detection & Monitoring
Log Indicators:
- Multiple failed authentication attempts followed by successful admin login
- Unusual firmware update or configuration change activities
Network Indicators:
- Unexpected outbound connections from iDRAC interfaces
- Traffic patterns suggesting buffer overflow attempts
SIEM Query:
source="idrac*" AND (event_type="authentication" AND result="success" AND user="admin") OR (event_type="firmware_update")