CVE-2022-40080
📋 TL;DR
This CVE describes a stack overflow vulnerability in the BIOS firmware of Acer Aspire E5-475G laptops. It allows local attackers to execute arbitrary code during the UEFI DXE phase, potentially gaining escalated privileges. Only users of the specific Acer laptop model are affected.
💻 Affected Systems
- Acer Aspire E5-475G
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with persistent malware installation at firmware level, allowing attackers to bypass operating system security controls and maintain persistence across OS reinstalls.
Likely Case
Local privilege escalation allowing attackers to gain administrative access to the system, potentially leading to data theft, lateral movement, or installation of additional malware.
If Mitigated
Limited impact if proper access controls prevent local execution by unauthorized users, though physical access or existing user compromise could still enable exploitation.
🎯 Exploit Status
Exploitation requires local access and knowledge of the vulnerability, but public proof-of-concept code exists in GitHub repositories.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: BIOS update from Acer
Vendor Advisory: https://www.acer.com/ac/en/US/content/support
Restart Required: Yes
Instructions:
1. Visit Acer support website. 2. Enter your laptop serial number. 3. Download latest BIOS update. 4. Run the BIOS update utility. 5. Restart system as prompted.
🔧 Temporary Workarounds
Restrict physical access
allLimit physical access to affected systems to authorized personnel only
Implement least privilege
allEnsure users only have necessary privileges to reduce impact of local exploitation
🧯 If You Can't Patch
- Isolate affected systems from critical networks and data
- Implement strict physical security controls and monitor for unauthorized access
🔍 How to Verify
Check if Vulnerable:
Check BIOS version in system settings or using manufacturer tools, compare against patched versions from AcerCheck Version:
Windows: wmic bios get smbiosbiosversion | Linux: sudo dmidecode -s bios-versionVerify Fix Applied:
Verify BIOS version has been updated to latest version from Acer support site📡 Detection & Monitoring
Log Indicators:
- Unusual BIOS/UEFI access attempts
- Failed BIOS update attempts
- System restarts with BIOS modification warnings
Network Indicators:
- Unusual outbound connections following local privilege escalation
SIEM Query:
EventID=12 OR EventID=13 (System events showing unexpected shutdowns/restarts) combined with privilege escalation alerts