LogoFAIL: UEFI Vulnerabilities Expose Devices to Stealth Malware Attacks

The Unified Extensible Firmware Interface (UEFI) code from various independent firmware/BIOS vendors (IBVs) has been found vulnerable to potential attacks through high-impact flaws in image parsing libraries embedded into the firmware.

The shortcomings, collectively labeled LogoFAIL by Binarly, “can be used by threat actors to deliver a malicious payload and bypass Secure Boot, Intel Boot Guard, and other security technologies by design.”

Furthermore, they can be weaponized to bypass security solutions and deliver persistent malware to compromised systems during the boot phase by injecting a malicious logo image file into the EFI system partition.

While the issues are not silicon-specific, meaning they impact both x86 and ARM-based devices, they are also UEFI and IBV-specific. The vulnerabilities comprise a heap-based buffer overflow flaw and an out-of-bounds read, details of which are expected to be made public later this week at the Black Hat Europe conference.

Specifically, these vulnerabilities are triggered when the injected images are parsed, leading to the execution of payloads that could hijack the flow and bypass security mechanisms.

“This attack vector can give an attacker an advantage in bypassing most endpoint security solutions and delivering a stealth firmware bootkit that will persist in an ESP partition or firmware capsule with a modified logo image,” the firmware security company said.

In doing so, threat actors could gain entrenched control over the impacted hosts, resulting in the deployment of persistent malware that can fly under the radar.

Unlike BlackLotus or BootHole, it’s worth noting that LogoFAIL doesn’t break runtime integrity by modifying the boot loader or firmware component.

The flaws affect all major IBVs like AMI, Insyde, and Phoenix as well as hundreds of consumer and enterprise-grade devices from vendors, including Intel, Acer, and Lenovo, making it both severe and widespread.

The disclosure marks the first public demonstration of attack surfaces related to graphic image parsers embedded into the UEFI system firmware since 2009, when researchers Rafal Wojtczuk and Alexander Tereshkin presented how a BMP image parser bug could be exploited for malware persistence.

“The types – and sheer volume – of security vulnerabilities discovered […] show pure product security maturity and code quality in general on IBVs reference code,” Binarly noted.