CVE-2021-0116
📋 TL;DR
This vulnerability is an out-of-bounds write in Intel processor firmware that allows a privileged user to potentially escalate privileges via local access. It affects specific Intel processors and requires local access to exploit. The impact is limited to systems with affected Intel CPUs.
💻 Affected Systems
- Intel Processors with specific firmware versions
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
A privileged attacker could gain kernel-level access, potentially compromising the entire system and accessing sensitive data or installing persistent malware.
Likely Case
A local attacker with existing privileges could elevate to higher system privileges, potentially bypassing security controls.
If Mitigated
With proper access controls and monitoring, the impact is limited to authorized users who already have some level of system access.
🎯 Exploit Status
Requires local access and privileged user credentials. Exploitation involves firmware manipulation which is complex.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Updated firmware/microcode from Intel
Vendor Advisory: https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00527.html
Restart Required: Yes
Instructions:
1. Check Intel SA-00527 for affected processors. 2. Obtain updated firmware/microcode from Intel or system manufacturer. 3. Apply firmware update following manufacturer instructions. 4. Reboot system to activate new firmware.
🔧 Temporary Workarounds
Restrict local access
allLimit physical and remote local access to affected systems to reduce attack surface
Implement least privilege
allEnsure users only have necessary privileges to limit potential privilege escalation impact
🧯 If You Can't Patch
- Isolate affected systems from critical networks and sensitive data
- Implement strict access controls and monitoring for systems with affected processors
🔍 How to Verify
Check if Vulnerable:
Check processor model and firmware version against Intel SA-00527 advisory. Use system BIOS/UEFI or OS commands to check current firmware version.Check Version:
Linux: 'cat /proc/cpuinfo' or 'dmidecode -t bios'; Windows: 'wmic bios get smbiosbiosversion' or 'systeminfo'Verify Fix Applied:
Verify firmware version has been updated to patched version listed in Intel advisory. Check system logs for successful firmware update.📡 Detection & Monitoring
Log Indicators:
- Failed firmware update attempts
- Unauthorized BIOS/UEFI access attempts
- Privilege escalation attempts
Network Indicators:
- None - local access only vulnerability
SIEM Query:
Search for BIOS/UEFI modification events or privilege escalation patterns on systems with affected Intel processors