Command format-string-helper

The format-string-helper command will create a GEF specific type of breakpoints dedicated to detecting potentially insecure format string when using the GlibC library.

It will use this new breakpoint against several targets, including:

  • printf()
  • sprintf()
  • fprintf()
  • snprintf()
  • vsnprintf()

Just call the command to enable this functionality. fmtstr-helper is an alias of format-string-helper.

gef➤ fmtstr-helper

Then start the binary execution.

gef➤ g

If a potentially insecure entry is found, the breakpoint will trigger, stop the process execution, display the reason for trigger and the associated context.

fmtstr-helper-example