Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

How to patch vulnerability of bash in Altera Cygwin (Shellshock bug)

cygwin (https://cygwin.com/ml/cygwin-announce/2014-10/msg00004.html) is included in several Altera tooling. It is a Unix-like environment within Windows. Therefore I post this question in "Other Operating Systems".

The bash shell that comes with Altera tooling such as Quartus and EDS is vulnerable for the shellshock (http://en.wikipedia.org/wiki/shellshock_%28software_bug%29) bug.

We are using several older and newer Altera versions: 9.1, 11.0sp1, 12.1sp1, 13.1 and 14.0. The bash shells that come with this tooling are all vulnerable.

Does anyone know how to patch them? Can I replace an older bash with the newest one with backwards compatibility? Will the older toolchains still work?

To test if bash is vulnerable start the "Nios II Command Shell.bat" or "Embedded_Command_Shell.bat" and run the following command within it:

env 'x=() { echo vulnerable; }' bash -c x

If it prints "x: command not found", your version of bash is safe and not subject to remote exploits. If it prints "vulnerable", you need to upgrade.

We have the following versions:

C:\altera\91\nios2eds\Nios II Command Shell.bat

C:\altera\11.0sp1\nios2eds\Nios II Command Shell.bat

C:\altera\12.1sp1\nios2eds\Nios II Command Shell.bat

C:\altera\13.1\nios2eds\Nios II Command Shell.bat

C:\altera\14.0\embedded\Embedded_Command_Shell.bat

C:\altera\14.0\nios2eds\Nios II Command Shell.bat

6 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    11 years ago

    Firstly, that is the wrong test for the vulnerability, better is: 

    x='() { fubar; }; echo barfu' sh -c ""

    Which should not output 'barfu'.

    But I wouldn't worry about it on your development system, most things that can set environment variables can just execute the relevant command instead.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    11 years ago

    --- Quote Start ---

    But I wouldn't worry about it on your development system, most things that can set environment variables can just execute the relevant command instead.

    --- Quote End ---

    Besides development systems we have also installed these Altera tools (with Cygwin) on build servers. Should we patch them? If so, how should we do that without breaking backwards compatibility?
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    11 years ago

    Just ensure that whatever executes the Altera tools doesn't have anything 'nasty' in it's 'environment variables'.

    I'd guess the 'environment variables' come straight from the windows ones.

    Unless these are set based on information from an untusted remote system (which I doubt) it just doesn't matter.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    11 years ago

    Altera is aware of this and will be addressing it. I can't commit to a date but it's on our radar.