[synnergy] - Solaris mailtool(1) buffer overflow vulnerability

From: dethy (dethyat_private)
Date: Mon May 28 2001 - 02:46:13 PDT

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    Vulnerability in Solaris mailtool(1)
    
    Date Published: May 29, 2001
    
    Advisory ID: N/A
    
    Bugtraq ID: N/A
    
    Sun Bug ID: 4458476
    
    CVE CAN: Non currently assigned.
    
    Title: Solaris mailtool(1) Buffer Overflow Vulnerability
    
    Class: Boundary Error Condition
    
    Remotely Exploitable: No
    
    Locally Exploitable: Yes
    
    Vulnerable Packages/Systems:
    
    Solaris 8       x86
    Solaris 8       sparc
    [possibly others]
    
    Discovery: dethyat_private
    
    Synopsis:
    
    The mailtool program is installed setgid mail by default in Solaris,
    a buffer overrun exists in the OPENWINHOME environment variable. By
    specifying a long environment buffer containing machine executable code,
    it is possible to execute arbitrary command(s) as gid mail.
    
    Analysis:
    
    The vulnerability in mailtool incorrectly handles data from the
    OPENWINHOME environment variable, if this variable exceeds a predefined
    length a stack overflow can occur.
    
    
     bash-2.03# export OPENWINHOME=`perl -e 'print "A"x1010'`
     bash-2.03# mailtool
     Segmentation Fault
    
     `truss` output:
        Incurred fault #6, FLTBOUNDS  %pc = 0xDF8BD448
        siginfo: SIGSEGV SEGV_MAPERR addr=0x4141414D
        Received signal #11, SIGSEGV [default]
        siginfo: SIGSEGV SEGV_MAPERR addr=0x4141414D
        *** process killed ***
    
    
    Quick Fix:
    
    Clear the sgid bit off the /usr/openwin/bin/mailtool program.
    chmod -s `which mailtool`
    
    Solution/Vendor:
    
    Sun Microsystems was notified on May 14, 2001 and verified the
    vulnerability. Patches/fixes are shortly to be released.
    
    Related Links:
    
    This vulnerability is unrelated to the Solaris 7/8 ximp40 shared library
    overflow discovered earlier in the year:
    http://www.securityfocus.com/archive/1/159586
    
    Credits :
    
    Vulnerability discovered by dethy (dethyat_private)
    
    Synnergy Networks http://www.synnergy.net
    



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