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Re: CVE-2014-6271: remote code execution through bash


From: Chet Ramey <chet.ramey () case edu>
Date: Sat, 27 Sep 2014 14:20:36 -0400

On 9/27/14, 2:17 PM, Chet Ramey wrote:

So what's your opinion on the appropriate set of restrictions? This is a
question that goes farther than what a particular shell will import,
since I'm going to align the restrictions on what functions a shell will
import from the environment with what functions that shell will let a
user define.  That means that a posix-mode shell will require imported
functions to be valid identifiers, but a non-posix mode shell will allow
words.  The original check that was in bash-4.3 does this.  What additional
checks should there be? I can see starting with rejecting function names
that can be confused with pathnames.

Please chime in and let me know what you think.

Sorry, I should have added that I'm not interested in rehashing decisions
that were made 25 years ago, and I am completely aware that this "violates"
Posix.  (That's why it doesn't do this in posix mode.)

Chet

-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, ITS, CWRU    chet () case edu    http://cnswww.cns.cwru.edu/~chet/


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