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icon4.gif   ELOG security vulnerability fixed, IMPORTANT!!!!, posted by Stefan Ritt on Mon Feb 14 12:36:30 2005 
    icon4.gif   Re: ELOG security vulnerability fixed, IMPORTANT!!!!, posted by Recai Oktas on Mon Feb 14 18:49:44 2005 
Message ID: 941     Entry time: Mon Feb 14 12:36:30 2005     Reply to this: 943
Icon: Warning  Author: Stefan Ritt  Author Email: stefan.ritt@psi.ch 
Category: Info  OS: Linux | Windows  ELOG Version: 2.5.7 
Subject: ELOG security vulnerability fixed, IMPORTANT!!!! 
Dear ELOG users,

It has been brought to my attention that ELOG has a vulnerability through
which one can obtain a remote shell (meaning to log in to your machine
through elog). There is even an exploit available which demonstrates that
both for linux and windows.

This is a severe security problem for all logooks which can be seen from
outside, even if they have password protection on. I strongly recommened to
upgrade to elog version 2.5.7 as soon as possible if you run a public elog
server.

Here is some explanation for the technically interested:

The problem arises from a strcpy() in the decode_post() routine, which
triggers a buffer overflow when attachment file names longer than 256
characters are submitted. I replaced (hopefully) all strcpy() with strlcpy()
to fix this problem, but if someone sees a location which I have missed,
please tell me.

The second vulnerability had to do with write passwords. If you put a "write
password = xxx" statement into your config file, it was still possible to
download the config file with a special hand-written URL, and decode the
write password, which is usually only base-64 encoded unless you haven't
compiled elog with the -DHAVE_CRYPT flag. I have changed that so if a write
password is present, the download is only possible when this password is
submitted in each request. If this has some effects on synchronizing of
logbooks, please let me know.

Stefan Ritt
ELOG V3.1.5-fe60aaf