🚀 go-pugleaf

RetroBBS NetNews Server

Inspired by RockSolid Light RIP Retro Guy

Article View: comp.security.unix
Article #14

Re: Security hole with WU-FTPD

#14
From: mumford
Date: Mon, 18 Jan 1999 00:00
30 lines
2361 bytes
A while ago, Bill Unruh<unruh@physics.ubc.ca> begot:
>In <F5p6AI.569@scrum.muc.de> mibu@scrum.muc.de (M. Buchenrieder) writes:
>>and manually edit the /etc/passwd file to have an entry with an empty
>>password string and no corresponding entry in /etc/shadow, then you'll
>>always be able to login without password. Try it. Add a user manually
>>and login. I just tested it on a SuSE 5.3 system, using login.c v. 1.4 .
>>Using an FTP account to actually access the system is just a way to hide
>>the intruder(s) from the eyes of the sysadmin. But the damage is already
>>done.
>
>His comment is that while login does not allow a remote root login with no
>password, ftp does allow a root login with no password. This is what he
>is calling the bug in ftpd.  It certainly is an inconsistancy between
>the two.
>
>It is also true that this bug is minor compared to the bug which allowed
>a root user to be entered into passwd without a password.

In a way it is an inconsistancy, but in another way it isn't.  The linux
login program has been hacked (if you will) to pay attention to a file
called /etc/securetty (may vary from dstrib to distrib).  Wu-ftpd could
not care less about this file, since ftp doesn't open a tty.

It's not a bug, it's a feature. :)

-- 
Glenn Lamb - mumford@netcom.com.  Finger for my PGP Key.
Email to me must have my address in either the To: or Cc: field.  All other
mail will be bounced automatically as spam.
PGPprint = E3 0F DE CC 94 72 D1 1A  2D 2E A9 08 6B A0 CD 82
Technical Details
Message-ID: <mumfordF5rn4H.B0L@netcom.com>
Path: arc1-ca.pugleaf.net!unknown!not-for-mail
References: <369FBEFB.EB1531B6@gds.ca> <SS3o2.269$oD6.18936@burlma1-snr1.gtei.net> <F5p6AI.569@scrum.muc.de> <77tkol$b3b$1@nntp.ucs.ubc.ca>

Show Full Headers
Complete Article Headers
X-Google-Language: ENGLISH,ASCII-7-bit
X-Google-Thread: 10952f,e0782a6bf0e6f7aa
X-Google-Attributes: gid10952f,public
X-Google-Thread: 10669a,e0782a6bf0e6f7aa
X-Google-Attributes: gid10669a,public
X-Google-Thread: 102983,e0782a6bf0e6f7aa
X-Google-Attributes: gid102983,public
X-Google-Thread: fa777,e0782a6bf0e6f7aa
X-Google-Attributes: gidfa777,public
From: mumford@netcom.com (mumford)
Subject: Re: Security hole with WU-FTPD
Date: 1999/01/18
Message-ID: <mumfordF5rn4H.B0L@netcom.com>
X-Deja-AN: 434058659
Sender: mumford@netcom12.netcom.com
References: <369FBEFB.EB1531B6@gds.ca> <SS3o2.269$oD6.18936@burlma1-snr1.gtei.net> <F5p6AI.569@scrum.muc.de> <77tkol$b3b$1@nntp.ucs.ubc.ca>
Organization: ICGNetcom
Newsgroups: comp.security.unix,redhat.networking.general,aus.computers.linux,comp.os.linux.networking