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Lenovo Installed Software On Laptops That Persisted After Complete Wipes
An anonymous reader writes: The Next Web has confirmed reports from owners of Lenovo laptops that the company used a BIOS feature to install its software on the laptops even if a user wiped a device clean and reinstalled the operating system. "If Windows 7 or 8 is installed, the BIOS of the laptop checks 'C:\Windows\system32\autochk.exe' to see if it's a Microsoft file or a Lenovo-signed one, then overwrites the file with its own. Then, when the modified autochk file is executed on boot, another two files LenovoUpdate.exe and LenovoCheck.exe are created, which set up a service and download files when connected to the internet." Lenovo has published a patch to remove this functionality. The article notes that this technique seems to be sanctioned by a Microsoft policy. "Manufacturers are obligated to ensure that the mechanism can be updated if an attack is discovered and should be removable by the user, but the rules outlined in the document are fairly loose and don't require the OEM to notify the owner of the laptop that such a mechanism is in place."
When Windows auto-updates go horribly wrong, almost all users blame the h/w vendor, not Microsoft. So Lenovo uses this BIOS trick to protect their reputation. Why is this being depicted as malicious behaviour?
If you keep throwing chairs, one day you'll break windows....
Never buying from that company again and will, in my capacity as family tech support guy, ensure that nobody in my family buys one. Wow. That company cannot die quick enough.
This is actually a mechanism called Windows Platform Binary Table (WPBT).
More information can be found in the Microsoft WPBT whitepaper:
"This paper describes the format of a Windows Platform Binary Table (WPBT). The WPBT is a fixed Advanced Configuration and Power Interface (ACPI) table that enables boot firmware to provide Windows with a platform binary that the operating system can execute. The binary handoff medium is physical memory, allowing the boot firmware to provide the platform binary without modifying the Windows image on disk. In the initial version, the WPBT simply contains a physical address pointer to a flat, Portable Executable (PE) image that has been copied to physical memory. The WPBT is extensible, allowing the layout of published platform binaries to be more complex in future versions and allowing the support of more than one binary type.
It is expected that the binary pointed to by the WPBT is part of the boot firmware ROM image. The binary can be shadowed to physical memory as part of the initial bootstrap of the boot firmware, or it can be loaded into physical memory by extensible boot firmware code prior to executing any operating system code. A boot firmware component would create the WPBT based on the location of the platform binary. During operating system initialization, Windows will read the WPBT to obtain the physical memory location of the platform binary. In the first version, the binary is required to be a native, user-mode application that is executed by the Windows Session Manager during operating system initialization. Windows will write the flat image to disk, and the Session Manager will launch the process. Windows may reclaim the physical memory described in the WPBT.
If Windows observes a WPBT during operating system initialization, it will attempt to use an ACPI control method to communicate binary execution status back to the platform."
When I briefly worked inventory in 2008, Google management was thinking of abandoning Lenovo laptops as they kept finding backdoors for Chinese hackers in the BIOS. Not sure if they ever did. On the few contract assignments I've done for Google since then, everyone I worked with had a MacBook Pro laptop.
Sorry, but this is what happens when you let a country under the sway of a totalitarian government build you computers.
But isn't Lenovo based in China these days, not America?
Tell me your thoughts on the NSA and FBI please
Do NOT buy an NSA or FBI laptop.
It isn't just Lenovo. On most major brands of PC laptops, there is a BIOS setting that once set, can't be unset, which either enables LoJack for Laptops permanently, or permanently disables it. If it is set, it will always load the LoJack executables when Windows is installed, even if the hard disk is blank and the install media is clean.
Of course, this is a mechanism that can be both used for good or ill... I wouldn't be surprised to see BIOS attacks that allow an attacker to flash a Trojan dropper which will always be present even on a reinstall with the only fix being either a firmware upgrade (if the attacker didn't already block that), or replacement hardware. The only real way to prevent it is to virtualize everything, with the bare metal OS as thin as possible [1].
[1]: Would be nice to see something like VMWare ESXi, except with the ability to use the console graphically, one step up from a dumb terminal.
... install Windows ...
I think I just found how to fix it. Don't install Windows!
Slashdot still doesnâ(TM)t support Unicode after it was added to the HTML standard in 1997.
Deliberately replacing a file I've installed with one of their own sure seems like intentional damage to me.
"National Security is the chief cause of national insecurity." - Celine's First Law
On the plus side, the script kiddie might have a somewhat tricky time of it. On the minus side, if the OEM doesn't cave, or is actively hostile, you are also going to have a nasty time of it.
Suitably recent Intel CPUs have 'Intel boot guard'(Just above the middle of page 4). Apparently, in practice, basically all the vendors ship in 'Verified boot' mode. Their public key is fused in to the silicon at the factory; and if the appropriate private key wasn't used to sign the firmware, no dice.
The 'measured boot' capability is a bit more interesting; but largely moot because nobody uses it. I wouldn't put it past an OEM to somehow screw this up; but all reasonably contemporary laptops are not going to take kindly to 3rd party firmware.