Google » Toolbar : Security Vulnerabilities, CVEs,

The Google toolbar 1.1.58 and earlier allows remote web sites to perform unauthorized toolbar operations including script execution and file reading in other zones such as "My Computer" by opening a window to tools.google.com or the res: protocol, then using script to modify the window's location to the toolbar's configuration URL, which bypasses the origin verification check.

The Custom Button Installer dialog in Google Toolbar 4 and 5 beta presents certain domain names in the (1) "Downloaded from" and (2) "Privacy considerations" sections without verifying domain names, which makes it easier for remote attackers to spoof domain names and trick users into installing malicious button XML files, as demonstrated by presenting www.google.com when the button was downloaded from an arbitrary site through an open redirector on www.google.com.

The Google toolbar 1.1.58 and earlier allows remote web sites to monitor a user's input into the toolbar via an "onkeydown" event handler.

Cross-site scripting (XSS) vulnerability in Google Toolbar 2.0.114.1 allows remote attackers to inject arbitrary web script via about.html in the About section. NOTE: some followup posts suggest that the demonstration code's use of the res:// protocol does not cross privilege boundaries, since it is not allowed in the Internet Zone. Thus this might not be a vulnerability.

The Google toolbar 1.1.60, when running on Internet Explorer 5.5 and 6.0, allows remote attackers to cause a denial of service (crash with an exception in oleaut32.dll) via malicious HTML, possibly related to small width and height parameters or an incorrect call to the Google.Search() function.