
Critical UEFI Flaw: Microsoft-Signed Module Lets Hackers Bypass Secure Boot!
2025-06-15
Author: Li
A Dangerous UEFI Vulnerability Exposed
In a shocking revelation, hackers may have found a way to sneak around Secure Boot protections, presenting a serious threat to countless Windows laptops and servers. This stealthy attack can disable Secure Boot, a crucial security feature that guards against the loading of malicious software. While Microsoft has rolled out a patch, attackers would still need administrative and physical access to exploit this vulnerability.
A Chilling Insight into UEFI Flaws
This discovery shines a bright spotlight on the increasing number of vulnerabilities within the Unified Extensible Firmware Interface (UEFI) firmware—the essential standard for initializing hardware during the boot process of Windows and Linux systems. Because UEFI operates before the operating system and its defenses kick in, it has become an attractive target for cybercriminals.
Inside the Dangerous Module
Researchers from Binarly uncovered a troubling module, discovered on Virus Total last November, seemingly created by a vendor specializing in rugged displays commonly seen in public spaces like airports. This module holds a critical flaw labeled CVE-2025-3052, rooted in UEFI memory corruption vulnerabilities. Armed with a Microsoft third-party certificate, the module enables attackers to overwrite a key variable necessary for maintaining Secure Boot.
How the Vulnerability Works
The report describes that the module accesses the UEFI IhisiParamBuffer variable and improperly uses it as a pointer for multiple memory write operations without validating it. This breach allows hackers to manipulate the variable, granting them unprecedented control over memory operations. The IhisiParamBuffer is crucially stored in non-volatile RAM, which retains data between boots, making it a frequent target for exploitation.
Not All Systems Are Affected
While some UEFI distributions effectively protect against this exploit by treating the IhisiParamBuffer variable as read-only, the majority of systems remain under threat, according to Binarly. In a concerning twist, the researchers noted that this compromised module might have been in circulation online since October 2022.
Immediate Responses and Further Discoveries
When Binarly informed Microsoft about this dangerous flaw, the tech giant discovered that 13 other firmware modules shared the same vulnerability. As a result, Microsoft decided to invalidate the certificates for all 14 modules during their June Patch Tuesday release, aiming to curb the potential fallout.
Stay Vigilant: The Ongoing Battle Against Cybersecurity Threats!
This incident underscores a chilling reality for users: even trusted vendors can have vulnerabilities that put systems at risk. As cyber threats continue to evolve, staying alert and up-to-date with security patches is imperative for safeguarding sensitive data and maintaining system integrity. The battle against cybercrime is far from over!