Qualys Vulnerability & Malware Research Labs (VMRL) http://www.qualys.com http://www.dissect.pe Memory corruption when Apple Quicktime parsers .pct file CVE-2012-0671 INTRODUCTION Apple Quicktime does not properly parse .pct media files, which causes a corruption in module DllMain by opening a malformed file with an invalid value located in PoC repro01.pct at offset 0x20E. This problem was confirmed in the following versions of Quicktime and Windows, other versions may be also affected. Quicktime Player version 7.7.1 (1680.42) on Windows XP SP 3 - PT_BR. Apple addressed the vulnerability in the May's Quicktime Patchset (http://support.apple.com/kb/HT1222) CVSS Scoring System The CVSS score is: 8.6 Base Score: 10 Temporal Score: 8.6 We used the following values to calculate the scores: Base score is: AV:N/AC:L/Au:N/C:C/I:C/A:C Temporal score is: E:POC/RL:U/RC:UR TRIGGERING THE PROBLEM To trigger the problem a PoC file (repro01.pct) is available to interested parties. DETAILS (f28.c24): Access violation - code c0000005 (first chance) First chance exceptions are reported before any exception handling. This exception may be expected and handled. eax=02a70000 ebx=04402c68 ecx=98b1cc15 edx=00000004 esi=00000000 edi=088a5000 eip=6682ead8 esp=0012bfa8 ebp=00000001 iopl=0 nv up ei pl nz ac pe nc cs=001b ss=0023 ds=0023 es=0023 fs=003b gs=0000 efl=00210216 *** ERROR: Symbol file could not be found. Defaulted to export symbols for C:\Arquivos de programas\QuickTime\QTSystem\QuickTime.qts - QuickTime!DllMain+0x2d068: 6682ead8 668907 mov word ptr [edi],ax ds:0023:088a5000=???? 0:000> !exploitable Exploitability Classification: EXPLOITABLE Recommended Bug Title: Exploitable - User Mode Write AV starting at QuickTime!DllMain+0x000000000002d068 (Hash=0x0e483076.0x0e507376) User mode write access violations that are not near NULL are exploitable. CREDITS This vulnerability was discovered by Rodrigo Rubira Branco (http://twitter.com/bsdaemon) from the Qualys Vulnerability & Malware Research Labs (VMRL).