Microsoft Discovers GRUB2, U-Boot, and Barebox Bootloader Flaws with Copilot

Microsoft has disclosed the discovery of multiple critical vulnerabilities within the GRUB2, U-Boot, and Barebox bootloaders, leveraging its AI-driven Security Copilot platform for advanced threat analysis.

These bootloaders, integral to the Unified Extensible Firmware Interface (UEFI) Secure Boot framework and widely deployed in embedded systems, were found to contain exploitable flaws that could compromise system integrity, enable privilege escalation, and bypass Secure Boot protections.

The findings have significant implications for device security across Linux-based systems and embedded environments.

Technical Analysis of Vulnerabilities

The vulnerabilities uncovered span critical areas of bootloader functionality, particularly in filesystem parsing routines.

In GRUB2, integer overflow vulnerabilities were identified in symbolic link handling within filesystem modules such as JFS, UDF, and HFS.

These flaws could allow attackers to craft malicious filesystems that trigger memory corruption or arbitrary code execution during bootloader execution.

Exploitation of these vulnerabilities poses a direct threat to Secure Boot mechanisms by enabling ...