CVE-2025-2486
📋 TL;DR
This CVE allows attackers to bypass Secure Boot restrictions by accessing the UEFI Shell in Ubuntu systems with vulnerable edk2 firmware. This could enable booting unauthorized operating systems or loading malicious kernel modules. Affects Ubuntu systems with specific edk2 firmware versions.
💻 Affected Systems
- Ubuntu edk2 UEFI firmware
📦 What is this software?
Edk2 by Tianocore
Edk2 by Tianocore
⚠️ Risk & Real-World Impact
Worst Case
Complete Secure Boot bypass allowing persistent rootkit installation, OS compromise, and firmware-level persistence
Likely Case
Bypass of Secure Boot to load unauthorized kernel modules or boot alternative operating systems
If Mitigated
Secure Boot remains enforced if proper firmware updates are applied
🎯 Exploit Status
Requires physical access or administrative privileges to access UEFI/BIOS settings
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2024.05-2ubuntu0.3 or 2024.02-2ubuntu0.3
Vendor Advisory: https://bugs.launchpad.net/ubuntu/+source/edk2/+bug/2101797
Restart Required: Yes
Instructions:
1. Update system: sudo apt update && sudo apt upgrade
2. Reboot system to apply firmware update
3. Verify Secure Boot status in UEFI settings
🔧 Temporary Workarounds
Disable UEFI Shell in firmware settings
allManually disable UEFI Shell access in system BIOS/UEFI settings
Enable Secure Boot with custom keys
linuxReplace default Secure Boot keys with organization-controlled keys
🧯 If You Can't Patch
- Restrict physical access to vulnerable systems
- Implement strict administrative access controls and monitoring
🔍 How to Verify
Check if Vulnerable:
Check edk2 package version: dpkg -l | grep edk2Check Version:
dpkg -l | grep edk2Verify Fix Applied:
Verify package version is 2024.05-2ubuntu0.3 or 2024.02-2ubuntu0.3 or later📡 Detection & Monitoring
Log Indicators:
- UEFI/BIOS configuration changes
- Secure Boot status changes in system logs
SIEM Query:
Search for UEFI/BIOS configuration change events or Secure Boot status alerts