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  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]
Date: Sun Oct  9 17:41:44 2005
From: fosforo at gmail.com (F├│sforo)
Subject: Local suid files and buffer overflows

try copying /bin/bash to /tmp/ directory, setting suid for all

t+

2005/10/9, Joachim Schipper <j.schipper@...h.uu.nl>:
> On Sun, Oct 09, 2005 at 01:17:39AM +0200, Werner Schalk wrote:
> > Hi,
> >
> > first of all apologies for asking such a newbie question but I am trying
> > to learn how to exploit buffer overflows and therefore wrote a little
> > program to exploit. This little program has the following permissions:
> >
> > $ ls -la test1
> > -rwsr-sr-x  1 root root 17164 Oct  8 01:25 test1
> >
> > Now I exploited it using Aleph One's shellcode (see
> > http://shellcode.org/shellcode/linux/null-free/) but I won't get a SUID
> > shell afterwards (I know the exploit did work but I still have my normal
> > user privleges). Why? I have tried a different shellcode to write a file
> > and this file was root:root. Any ideas, hints, rtfm?
> >
> > Thank you.
> >
> > Best regards,
> > Werner.
>
> Try the following:
>
> # mount
> <snippity>
> /dev/hdb2 on /home type ext3 (rw,nosuid,nodev)
> <snippity>
>
> nosuid means that suid binaries lose their special properties here.
> See mount(8). As you just proved, it's not completely useless.
>
> As an additional exercise, bypass the nosuid mount option. Or just copy
> it somewhere without nosuid.
>
> (There are many, many other ways this behaviour could have happened, but
> this one sounds most likely...)
>
>                 Joachim
> _______________________________________________
> Full-Disclosure - We believe in it.
> Charter: http://lists.grok.org.uk/full-disclosure-charter.html
> Hosted and sponsored by Secunia - http://secunia.com/
>


--

---------------------------------------------------------
>>>F?sforo<<<

Powered by blists - more mailing lists