ONN Laptop BIOS Exploration

ONN Splash


I recently acquired an ONN Laptop. This is a brand of laptop sold exclusively through Walmart in the US.

I decided to investigate this laptop because I had a suspicion it’s BIOS was not particularly locked down. Turns out my suspicion was well founded; this article will describe the various configuration settings made available through BIOS on the ONN Laptop.

I was unable to conduct extensive vulnerability testing with this laptop as by setting a particular BIOS option, through the built-in BIOS Configuration Utility nonetheless, I bricked the laptop. Read the analysis section for more information, where I also list out the various attacker vectors I identified.


Through the configuration menus listed below it is possible to enable Intel DCI without making any custom modifications to the BIOS image using a tool such as RU.efi. This means it is possible to enable Intel DCI without disabling and re-enabling Secure Boot. I was able to connect the laptop to a host system running Intel System Debugger (legacy) and successfully halt the laptop’s processor and see the system state, as well as perform some rudimentary debugging at this level.

The interesting functions of the BIOS - specifically the network enabled capabilities, do not seem to function properly. Every time I tried setting a boot URI in the UEFI HTTP IPv4 configuration menu, the option value reset to blank every time I saved the BIOS configuration.

Several other options, such as ASF Support in Advanced / AMT Configuration also displayed this behavior. When I set ASF Support to enabled, saved, and then exited the BIOS, on the very next entry into BIOS the ASF Support option was set to disabled.

I was able to get the WiFi configuration to successfully authenticate to the WiFi network, but the device never responded to ICMP or other IP level messages. It seems like there is some Layer 2 attack surface here in terms of authenticating to the WiFi access point, which may be the only “remote” attack vector. This still would require local proximity to the device.

Other interesting input includes the Cert Enrollment option in the Advanced / TLS Configuration menu. This allows certificates to be loaded from USB storage, which invites some unique opportunities, given physical access.

There of course are the UEFI NVRAM variables as potential vectors to supply malicious input. I did not explore this avenue beyond setting options in the BIOS configuration utility.

Also worth noting is that the Firmware Configuration Menu contains an option for Ignore Policy Update - when I set this to be the configured option, the laptop would no longer boot, not even to BIOS, resulting in a bricked laptop. It looks like the BIOS manufacturer attempted to warn users about setting this option, but it was not clear to me that setting this option as the configured value would have the effect of bricking the laptop.

I might have been able to restore the laptop to a functional state if I had made a back up of the SPI ROM prior to testing; I did not do this, foolishly not thinking that there could be any way to permanently brick the laptop through BIOS shy of powering off the device during a firmware update. Certainly I did not anticipate a configurable option placing the laptop in such a state.

The best advice I can offer users of this laptop is that they set the User Password under the Security Menu - this will require a password to POST as well as access BIOS settings. I’m not convinced that there isn’t a way to bypass this authentication mechanism, but it is better than nothing. Like most devices, physical access to this device essentially means game over in terms of security - by allowing debug capabilities it is possible to manipulate the laptop at the platform level.

Below is a run through of the BIOS Configuration Utility menus. Note that except for one or two special instances, the values in the images for the various settings are the default values.

ONN BIOS Main Menu

This is the first screen the user is greeted with upon entering system BIOS. The user can enter the system BIOS by pressing the Delete button at the ONN splash screen. It contains version information for the currently install BIOS image.

There are six total menus:

Advanced Menu

The advanced menu is where most BIOS configuration options are set. This includes the following sub-menus:

There are a few additional Networking menus that appear once Network Stack is enabled and the BIOS settings have been saved and the system reset. Those are:

We will explore these last five menus near the end of this post.

Advanced / RC ACPI Settings

ONN BIOS Advanced / RC ACPI Settings

This seems to be a power management and monitoring subsystem of the chipset. It contains a number of sub-menus:

Advanced / Connectivty Menu

ONN BIOS Advanced / Connectivity Menu

The Advanced / Connectivity Menu is used to configure onboard chip detection for communications chips, such as Bluetooth and WWAN.

Advanced / CPU Configuration Menu

ONN BIOS Advanced / CPU Configuration Menu

The Advanced / CPU Configuration menu details the L1-L4 cache information, as well as the processor ID and speed. Additioanlly, virtualization can be configured through this menu.

Advanced / Power & Performance Menu

0NN BIOS Advanced / Power Management Menu

The Power & Performance Menu allows the user to configure CPU and GT power options.

Advanced / PCH Menu

ONN BIOS Advanced / PCH Menu

The PCH Menu includes information on Intel ME, including version information. It allows various ME options to be set, including ME debug options.

Advanced / PCH Menu / ME Debug Settings

ONN BIOS Advanced / PCH Menu / ME Debug Settings

These are options for debugging Intel Management Engine. They include:

Advanced / Thermal Configuration Menu

ONN BIOS Advanced / Thermal Configuration Menu

The Advanced / Thermal Configuration Menu allows thermal configuration of CPU, Platform, and DPTF.

Advanced / Platform Settings Menu

ONN BIOS Advanced / Platform Settings Menu

The Advanced / Platform Settings Menu contains the following options:

Advanced / D3Cold Settings Menu

ONN BIOS Advanced / D3 Cold Settings Menu

The Advanced / D3 Cold Settings Menu includes the following options:

Advanced / Overclocking Configuration Menu

ONN BIOS Advanced / Overclocking Menu

The Advanced / Overclocking Menu allows the ability to enable/disable overclocking on the platform.

Advanced / Intel AMT Menu

ONN BIOS Advanced / Intel AMT Menu

The Advanced / Intel AMT Menu contains configuration options for Intel Active Management Technology. We will explore this capability further in the analysis section of this post.

The configuration options for this menu include:

Advanced / Intel ICC Menu

ONN BIOS Advabced / Intel ICC Menu

The Advanced / Intel ICC Menu includes the following configuration options:

The following configuration information is also presented:

Advanced / ThunderBolt(TM) Menu

ONN BIOS Advanced / ThunderBolt(TM) Menu

This menu allows the user to enabled/disable ThunderBolt(TM) support.

Advanced / Debug Settings Menu

ONN BIOS Advanced / Debug Settings Menu

This menu allows a user to configure Intel DCI, amongst other platform configuration options. The sub options in this menu are:

ONN BIOS Advanced / Debug Settings Menu / Platform Debug Consent

The options in this menu include:

I have set this option to Enabled (DCI OOB) so we can use DCI to debug the platform. More information on this will be provided in the analysis section.

Advanced / Debug Settings Menu / Advanced Debug Menu

ONN BIOS Advanced / Debug Settings Menu / Advanced Debug Menu

The Advanced / Debug Settings Menu / Advanced Debug Menu options are:

Advanced / Trusted Computing Menu

ONN BIOS Advanced / Trusted Computing Menu

The Advanced / Trusted Computing Menu contains TPM information as well as the following options:

Advanced / ACPI Menu

ONN BIOS Advanced / ACPI Menu

The Advanced / ACPI Menu contains the following configuration options:

Advanced / S5 Menu

ONN BIOS Advanced / S5 Menu

The Advanced / S5 menu allows the user to enable / disable Wake From S5.

Advanced / SMART Menu

ONN BIOS Advanced / SMART Menu

The Advanced / SMART Menu allows the user to enable / disable SMART.

Advanced / Serial Port Console Redirection Menu

ONN BIOS Advanced / Serial Port Console Redirection Menu

The Advanced / Serial Port Console Redirection Menu has the following options:

Advanced / Acoustic Management Configuration

ONN BIOS Advanced / Acoustic Management Configuration Menu

The Advanced / Acoustic Mangement Configuration Menu allows the user to enable / disable acoustic management of a given SATA device.

Advanced / Switchable Graphics Menu

ONN BIOS Advanced / Switchable Graphics Menu

Advanced / AMT Graphics Menu

ONN BIOS Advanced / AMT Graphics Menu

The Advanced / AMT Graphics Menu allows the user to set the output for AMT Graphics.

Advanced / PCI Settings Menu

ONN BIOS Advanced / PCI Settings Menu

The Advanced / PCI Settings Menu allows BME DMA Mitigation to be enabled / disabled.

Advanced / USB Settings Menu

ONN BIOS Advanced / USB Settings Menu

The Advanced / USB Settings menu contains the following configuration options:

Advanced / CSM Menu

ONN BIOS Advanced / CSM Menu

Advanced / NVMe Menu

ONN BIOS Advanced / NVMe Menu

Advanced / SDIO Menu

ONN BIOS Advanced / SDIO Menu

Advanced / RAM Disk Menu

ONN BIOS Advanced / RAM Disk Menu

Advanced / Networking Stack Menu

ONN BIOS Advanced / Networking Stack Menu

Advanced / Networking Options Menus

These next few networking stack-related options are only visible if networking has been enabled.

Advanced / VLAN Menu

ONN BIOS Advanced / VLAN Menu

Advanced / Ethernet Interface Menu

ONN BIOS Advanced / Ethernet Interface Menu

Advanced / UEFI HTTP Boot Menu

ONN BIOS Advanced / UEFI HTTP Boot Menu

Advanced / Ethernet Menu

ONN BIOS Advanced / Ethernet Menu

Advanced / WiFi Menu

ONN BIOS Advanced / WiFi Menu

Chipset Menu

ONN BIOS Chipset Menu

The chipset menu contains a few additional platform configuration options. The sub-menu’s available here are:

Note that by default, the Firmware Configuration is set to [Test].

ONN BIOS Firmware Configuration Options

Additional options for Firmware Configuration include:

Chipset / Graphics Configuration

ONN BIOS Chipset / Primary Display Menu

The following options are availabe for primary display:

I set this option to PCI to work with my HDMI capture card. By default it is set to auto.

Security Menu

ONN BIOS Security Menu

The Security menu allows the user to set an Administrator Password or a User Password. The Administrator Password allows access to BIOS Setup, while the User Password allows POST and access to BIOS Setup.

Additionally, Secure Boot can be configured in this menu.

Security / Secure Boot Menu

ONN BIOS Security / Secure Boot Menu

There are two options for Secure Boot Mode:

ONN BIOS Security / Secure Boot Mode Options

Note the Secure Boot is enabeld by default.

Boot Menu

The Boot Menu presents the user with options as to boot device order.

Save & Exit Menu

The Save & Exit Menu presents the user with options to save BIOS configuration settings as well as to override the boot settings

Update 10/13/2021

@RockerFernando reached out to me with some additional details. Apparently there are Gateway-branded laptops that have the same BIOS as the ONN-branded laptop. Like me, he had bricked his laptop by setting the same BIOS option. I was pretty sure that by resetting the NVRAM we could restore our laptops to a usable state, and @RockerFernando went and figured out how to do this. If you open the chassis and disconnect the battery, or simply wait a few months until the battery is totally dead, and then hold down the power button for about a minute, you should be able to reset NVRAM thus clearing the faulty configuration value. Thanks @RockerFernando for the tip!