Apple has pushed iOS 4.2.8 for Verizon iPhone 4 (CDMA). You can download iOS 4.2.8 for Verizon iPhone 4. GSM iPhone 4 users can download iOS 4.3.3. Both the iOS 4.2.8 and 4.3.3 bring fix for the iOS location tracking bug.
How to Restore iOS 4.2.8
*** iOS 4.2.8 requires iTunes 10.2.2
Connect your Verizon iPhone 4 to iTunes 10.2.2, firmware 4.2.8 availability message will appear then hit the “Download and Install” [Mac OS X] or “Download and Update” [Windows] button to install iOS 4.2.8. (Not a recommended way for jailbreakers and unlockers)
You can also download iOS 4.2.8 firmware from the link below. Hold down the Shift (Windows) or Alt/Option (Mac) key and hit the restore button on iTunes and select the downloaded IPSW file.
Download iOS 4.2.8
Direct link to download iOS 4.2.8 firmware (IPSW files) links for Verizon iPhone 4: