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wiki:security:rbash [2014/10/31 22:11]
woglinde [Link the needed programs to setup a session]
wiki:security:rbash [2014/11/03 13:07] (current)
woglinde [rbash as default shell (optional)]
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-The way x2go works, allows every user to get ssh access to the x2go server.+The way x2go works, allows every user to get ssh access to the x2go server.
  
 This can be a big problem when, you can not use the broker, to prevent certain actions on This can be a big problem when, you can not use the broker, to prevent certain actions on
-the server. The users can browse the x2go-server and have the access to nearly all directiores.+the x2go-server. 
 + 
 +The users can browse the x2go-server and have the access to nearly all directiores.
  
 There are serval options to prevent the user doing it. One would be the use of selinux, but it is hard to understand There are serval options to prevent the user doing it. One would be the use of selinux, but it is hard to understand
 and hard to setup correctly. Another option is the use of rbash, but with the current state of x2go-server there and hard to setup correctly. Another option is the use of rbash, but with the current state of x2go-server there
 are serval steps so setup it up working correctly. are serval steps so setup it up working correctly.
 +
 +This guide is focused on a single application approach, no audio, remote/mounted dirs and printing are involved.
  
 ====== rbash short feature overview ====== ====== rbash short feature overview ======
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   * no redirections via > and >> are allowed   * no redirections via > and >> are allowed
   * no calls of binaries via complete path   * no calls of binaries via complete path
-  * no changes on the PATH variable are allowed+  * no changes off the PATH variable are allowed
  
 But be aware, if rbash detects that a executebale is a shell-script it will be run with full bash. But be aware, if rbash detects that a executebale is a shell-script it will be run with full bash.
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 export PATH=/bin:/usr/bin:/sbin:/usr/sbin export PATH=/bin:/usr/bin:/sbin:/usr/sbin
 </code> </code>
 +
 +===== Security concerns =====
 +There could be still problems to brake out of rbash, no one yet made a security audit of the linked x2go scripts, if they allow the execution of a real shell
 +via options.
 +
wiki/security/rbash.1414793472.txt.gz · Last modified: 2014/10/31 22:11 by woglinde