Recently released iOS 4.0.1 jailbreak uses PDF exploit to access your iPhone and patch iOS 4.0.1. Since the browser based jailbreak tool uses this critical exploit in Safari for iPhone, users are definite to feel vulnerable to security loophole. Using this vulnerability, hackers can make you download a PDF (without you knowing about it) that may install malicious code on iPhone.

iOS 4.0.1 PDF Exploit Warner
Since the JailbreakMe tool is now public, you can use PDF Loading Warner for iPhone or iPad from Cydia. This little tool will notify you each time a website attempts to make you download a PDF, so you can decide whether or not to download it.
How to Install PDF Loading Warner:
Step 1: Jailbreak iPhone with JailbreakMe
Step 2: Open Cydia and go to “Search” Tab
Step 3: Search for ”PDF Loading Warner”
Step 4: Install the app
That’s it. Now you can safely browse from Safari for iPhone without being fearful of getting hit by malicious code.