Vulnerability Development mailing list archives

openbsd 3.4 ps bug


From: thanos F@rm@k1s <fsvsunix () hotmail com>
Date: 19 Nov 2003 19:20:27 -0000




Security bug for openbsd 3.4

While i was testing my new openbsd 3.4 i found the following problem.
First of all i have the OpenBSD3.4 FUlly patched with all the latest 
fixes in an i386 machine (P3 128mb ram).Some of the ports were installed
too(From the oficial 3cd set which i bought).While i was playing with the
command ps i found the following which i have tested it in two machines with
four different kernels(2 patched and 2 unpatched).The utility ps has a flaw
when used with the bash shell.Go to your root(/) directory or any dir that 
contains more then two files or directorys and give the command ps -p * or 
ps -N * or ps -M * and you will instantly see a core dump file in your dir.
The ps program is giving us a signal (SIGSEGV).Please try all the above args
more then two times and first in your root dir.When i tried to confirm it with 
the gdb it gave me the address 0x1c01c116 in ?? ().I don`t have the 
time to confirm if the bug is exploitable or not but it is a big problem
because a user(id 1000+) can also do that.This is a report which will also 
be submited in the bugtraq.It is also not confirmed that other versions are
vulnerable to this bug.This bug can only be reproduced when bash2 is installed
(from the official ports package) and a in a dir where more then two files exists. 
Sorry for the bad englis.

The openbsd team has been informed.


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