I had UEFI Secure Boot enabled laptop with Windows 8 installed in, the problem is that I restored another OS(linux) and now I cannot enter in BIOS Setup.
Is there a way to disable UEFI Secure Boot without entering in BIOS settings?
By design, Secure Boot cannot be disabled from within an OS; you must enter your firmware's setup utility in order to disable it. With most computers, you can enter the firmware setup utility by hitting a function key, or sometimes Del, early in the boot process. Some computers don't enable the keyboard, though, or don't provide this option at all. If you've got such a system, you could try unplugging the hard disk from the motherboard and booting without a disk; that might kick the system into the firmware setup utility.
Another option would be to prepare a USB flash drive or the like with a Secure Boot-enabled boot loader (PreLoader or shim). This would enable you to boot to Linux and install the Secure Boot-enabled boot loader on your hard disk. If you use PreLoader, you can begin as just described, but you'll also need to copy a regular Linux boot loader to the USB drive as
Update: Recent versions of rEFInd, and I believe also gummiboot, provide an option to reboot into the firmware setup utility. To be useful, you'll need to install these programs to launch from
Secure Boot is an option enabled by default on UEFI OEM systems. Its actually required, to be turned on by default with the option to disable it, to be get a Windows 8 supported sticker from Microsoft.
So even if you remove the CMOS battery the default option would be to enable