full-disclosure - Symlink attack techniques

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <200512151309.49511.werner_schalk@gmx.de>
Date: Thu Dec 15 13:38:05 2005
From: werner_schalk at gmx.de (Werner Schalk)
Subject: Symlink attack techniques

Hi,

thanks for all the replies, I really appreciate this.

> Assuming that the find command will report a directory or file that you
> control, you can use the symlink to overwrite a shell script, and then
> place shell commands into your file name:

Ok I should have been more precise in my previous mail. In this scenario I 
don't have control over the output generated by the find command. So 
basically the cronjob is something like:

15 4 ?* * 6 ?root ?/usr/bin/find /home/userA -type f -print > /tmp/report.txt

Consequently as userB I have no way of influencing what information is printed 
by the find command to /tmp/report.txt but I can surely 
control /tmp/report.txt. Any other ideas of how to exploit this to gain root 
access?

Thank you very very much.

All the best,
Werner.