Known Security Problems
The following is a list of known security problems with the current
version of the plugin:
- The plugin does not implement resource controls. Thus, it is quite easy to
write Tcl scripts that successfully mount resource attacks such as
running in an infinite loop or computing an unbounded string.
- An applet can request a huge canvas and crash Tk because it cannot
allocate a pixmap large enough.
- Asking for large pointsize fonts can take a very long time (for instance
50 seconds to get Times 1000). And when you ask for a large Chinese font,
that can take 256 times longer! While it is fetching the font, the system is
effectively in a global grab & unresponsive: you can't ctrl-C the program or
click on another window and kill it. If you asked for Times 1<<30, you would
never get your system back.