Re: Bug#762839: bash without importing shell functions from the environment

2014-09-30 Thread Thorsten Glaser
On Fri, 26 Sep 2014, Matthias Urlichs wrote: In any case, adding -p to any #!/bin/bash shebang line looks like a very good idea. Shall we add a Lintian check for this? ***ABSOLUTELY NOT*** The -p option is for the shell to *not* drop privileges when called setuid. bye, //mirabilos --

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-30 Thread Matthias Urlichs
Hi, Thorsten Glaser: On Fri, 26 Sep 2014, Matthias Urlichs wrote: In any case, adding -p to any #!/bin/bash shebang line looks like a very good idea. Shall we add a Lintian check for this? ***ABSOLUTELY NOT*** The -p option is for the shell to *not* drop privileges when called

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-30 Thread Henrique de Moraes Holschuh
On Tue, 30 Sep 2014, Thorsten Glaser wrote: On Fri, 26 Sep 2014, Matthias Urlichs wrote: In any case, adding -p to any #!/bin/bash shebang line looks like a very good idea. Shall we add a Lintian check for this? ***ABSOLUTELY NOT*** The -p option is for the shell to *not* drop

Re: Re: Bug#762839: bash without importing shell functions from the environment

2014-09-28 Thread Raphael Geissert
On Friday 26 September 2014 18:48:37 Matthias Urlichs wrote: [...] In any case, adding -p to any #!/bin/bash shebang line looks like a very good idea. Shall we add a Lintian check for this? No. Cheers, -- Raphael Geissert - Debian Developer www.debian.org - get.debian.net -- To

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-28 Thread Matthias Urlichs
Hi, Raphael Geissert: On Friday 26 September 2014 18:48:37 Matthias Urlichs wrote: [...] In any case, adding -p to any #!/bin/bash shebang line looks like a very good idea. Shall we add a Lintian check for this? No. … and why not? Importing random functions from the environment is a

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-26 Thread Samuel Thibault
Nikolaus Rath, le Thu 25 Sep 2014 17:26:40 -0700, a écrit : Samuel Thibault sthiba...@debian.org writes: Matthias Urlichs, le Thu 25 Sep 2014 21:17:58 +0200, a écrit : Samuel Thibault: Sounds crazy to me. Definitely. This is now out in the wild; exploits which simply replace echo

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-26 Thread Samuel Thibault
Brian May, le Fri 26 Sep 2014 11:40:00 +1000, a écrit : On 26 September 2014 10:26, Nikolaus Rath [1]nikol...@rath.org wrote: Wasn't there some web server that used to put query script variables into the environment of the CGI script? Or am I confusing that with PHP's evil

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-26 Thread Josselin Mouette
Brian May br...@microcomaustralia.com.au wrote: On 26 September 2014 14:15, Russ Allbery r...@debian.org wrote: That would surprise me. In one case, you're setting an environment variable and then running sudo. In the other case,

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-26 Thread Vincent Lefevre
On 2014-09-26 09:19:17 +0200, Samuel Thibault wrote: Nikolaus Rath, le Thu 25 Sep 2014 17:26:40 -0700, a écrit : Wasn't there some web server that used to put query script variables into the environment of the CGI script? Well, that ought to have been fixed a long time ago already,

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-26 Thread Vincent Lefevre
On 2014-09-26 10:33:20 +0200, Josselin Mouette wrote: Brian May br...@microcomaustralia.com.au wrote: No, I don't think that is the case. I believe sudo interprets those assignments itself (as also shown in man page), and the error I got clearly shows this to be the

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-26 Thread shawn wilson
On Sep 25, 2014 3:18 PM, Matthias Urlichs matth...@urlichs.de wrote: Hi, Samuel Thibault: Sounds crazy to me. Definitely. This is now out in the wild; exploits which simply replace echo or cat-without-/bin are going to happen. :-/ Actually, what I've seen reported in the wild have been

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-26 Thread Matthias Urlichs
Hi, shawn wilson: Maybe we should add the patched version, with an appropriate NEWS entry, to backports? Maybe? Maybe we as a shorthand for IMHO, the maintainer of bash should. Better? :-) Also, '-p' (privileged mode, i.e. ignore functions in the environment, as well as a bunch of

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-25 Thread Samuel Thibault
Ian Jackson, le Thu 25 Sep 2014 16:29:05 +0100, a écrit : I have prepared bash packages which do not honour any shell functions they find in the environment. IMO that is a crazy feature, which ought to be disabled. (I'm running this on chiark now and nothing has visibly broken yet.) Yes. €

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-25 Thread Matthias Urlichs
Hi, Samuel Thibault: Sounds crazy to me. Definitely. This is now out in the wild; exploits which simply replace echo or cat-without-/bin are going to happen. :-/ Maybe we should add the patched version, with an appropriate NEWS entry, to backports? -- -- Matthias Urlichs signature.asc

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-25 Thread Samuel Thibault
Matthias Urlichs, le Thu 25 Sep 2014 21:17:58 +0200, a écrit : Samuel Thibault: Sounds crazy to me. Definitely. This is now out in the wild; exploits which simply replace echo or cat-without-/bin are going to happen. :-/ That's not so easy to exploit. You have to manage to inject those

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-25 Thread Nikolaus Rath
Samuel Thibault sthiba...@debian.org writes: Matthias Urlichs, le Thu 25 Sep 2014 21:17:58 +0200, a écrit : Samuel Thibault: Sounds crazy to me. Definitely. This is now out in the wild; exploits which simply replace echo or cat-without-/bin are going to happen. :-/ That's not so easy to

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-25 Thread Martin Uecker
Samuel Thibault: Matthias Urlichs, le Thu 25 Sep 2014 21:17:58 +0200, a écrit : Samuel Thibault: Sounds crazy to me. Definitely. This is now out in the wild; exploits which simply replace echo or cat-without-/bin are going to happen. :-/ That's not so easy to exploit. You have to

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-25 Thread Brian May
On 26 September 2014 10:26, Nikolaus Rath nikol...@rath.org wrote: Wasn't there some web server that used to put query script variables into the environment of the CGI script? Or am I confusing that with PHP's evil register_globals? CGI is just one avenue for attack. There are other

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-25 Thread Russ Allbery
Brian May br...@microcomaustralia.com.au writes: I thought sudo was suppose to be ok, sure doesn't look ok to me. brian@aquitard:~$ sudo echo='() { /bin/echo bar; }' bash root@aquitard:/home/brian# echo hello bar I think you have that backwards, don't you? Shouldn't that be: echo='()

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-25 Thread Russ Allbery
Martin Uecker uec...@eecs.berkeley.edu writes: While everybody is looking at bash, isn't this the real the injection part? Why are there still programs which copy stuff from the network into environment without proper sanitation? The previous sanitization for environment variables mostly

Re: Re: Bug#762839: bash without importing shell functions from the environment

2014-09-25 Thread Martin Uecker
Russ Allbery r...@debian.org: Martin Uecker uec...@eecs.berkeley.edu writes: While everybody is looking at bash, isn't this the real the injection part? Why are there still programs which copy stuff from the network into environment without proper sanitation? The previous sanitization

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-25 Thread Mike Hommey
On Thu, Sep 25, 2014 at 04:29:05PM +0100, Ian Jackson wrote: Package: bash Version: 4.1-3 I have prepared bash packages which do not honour any shell functions they find in the environment. IMO that is a crazy feature, which ought to be disabled. (I'm running this on chiark now and

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-25 Thread Brian May
On 26 September 2014 12:08, Russ Allbery r...@debian.org wrote: brian@aquitard:~$ sudo echo='() { /bin/echo bar; }' bash root@aquitard:/home/brian# echo hello bar I think you have that backwards, don't you? Shouldn't that be: echo='() { /bin/echo bar; }' sudo bash I think sudo

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-25 Thread Russ Allbery
Brian May br...@microcomaustralia.com.au writes: On 26 September 2014 12:08, Russ Allbery r...@debian.org wrote: I think you have that backwards, don't you? Shouldn't that be: echo='() { /bin/echo bar; }' sudo bash I think sudo treats both as the same/similar thing. That would

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-25 Thread Brian May
On 26 September 2014 14:15, Russ Allbery r...@debian.org wrote: That would surprise me. In one case, you're setting an environment variable and then running sudo. In the other case, you're telling sudo to run the command echo='() { /bin/echo bar; }' echo foo via a shell. No, I don't think

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-25 Thread Mike Hommey
On Fri, Sep 26, 2014 at 01:37:48PM +1000, Brian May wrote: On 26 September 2014 12:08, Russ Allbery r...@debian.org wrote: brian@aquitard:~$ sudo echo='() { /bin/echo bar; }' bash root@aquitard:/home/brian# echo hello bar I think you have that backwards, don't you? Shouldn't that

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-25 Thread Russ Allbery
Brian May br...@microcomaustralia.com.au writes: No, I don't think that is the case. I believe sudo interprets those assignments itself (as also shown in man page), and the error I got clearly shows this to be the case. brian@aquitard:~$ sudo echo='() { /bin/echo bar; id; }' ./test.sh

Re: Bug#762839: bash without importing shell functions from the environment

2014-09-25 Thread Matthias Urlichs
Hi, Martin Uecker: While everybody is looking at bash, isn't this the real the injection part? Why are there still programs which copy stuff from the network into environment without proper sanitation? Probably either sheer laziness, or for the usual, misguided-these-days (IMHO) be lenient