after the news of the release jailbreak apple tv 2 4.3 here is the step by step guide
Using Seas0nPass to jailbreak the AppleTV
Step 1: Unzip the ‘Seas0nPass.zip’ file and launch Seas0nPass.
Step 2: Select the ‘Create IPSW’ button to start the jailbreak process.
Step 3: The latest AppleTV software will be downloaded and used to create a custom ‘jailbroken’ software file.
Step 6: iTunes will confirm the restore when complete – your AppleTV is now jailbroken!
Using Seas0nPass for a ‘tethered boot’
Note: The tethered boot steps described below are not required for the current AppleTV 4.3 (8F455) software.
Some AppleTV software versions require a tethered boot. This means the AppleTV must be connected to a computer for a brief moment during startup.
Note: The AppleTV MUST be disconnected from the computer (for at least a brief moment) after restoring in iTunes for the tethered boot process below to work properly.
Step 1: Open Seas0nPass and select the ‘Boot Tethered’ option.
Step 3: Seas0n Pass will complete the tethered boot automatically. Once complete, remove the USB cable and connect the HDMI cable.
Note: Timing is key. Once the you receive the success message shown below, the USB cable should be removed and HDMI cable connected before the light on the front of the AppleTV stops flashing. (Don’t worry there is ample to do this, so you don’t need Superman speed).