[VulnWatch] [EEYEB-20050627B] Macromedia Flash Player Improper Memory Access Vulnerability

Date: 11/05/05

  • Next message: Advisories_at_eeye.com: "[VulnWatch] [EEYEB-20050901] Windows Metafile SetPalette Entries Heap OVerflow Vulnerability (Graphics Rendering Engine Vulnerability)"
    Date: Fri, 4 Nov 2005 17:30:15 -0800
    To: <bugtraq@securityfocus.com>, <vulnwatch@vulnwatch.org>, <ntbugtraq@ntbugtraq.com>, <full-disclosure@lists.grok.org.uk>

    Macromedia Flash Player Improper Memory Access Vulnerability

    Release Date:
    November 4, 2005

    Date Reported:
    June 27, 2005



    Systems Affected:
    Macromedia Flash 6 (on all Windows platforms)
    Macromedia Flash 7 (on all Windows platforms)

    eEye Digital Security has discovered a vulnerability in Macromedia Flash
    Player versions 6 and 7 that will allow an attacker to run arbitrary
    code in the context of the logged in user. An array boundary condition
    may be violated by a malicious SWF file in order to redirect execution
    into attacker-supplied data.

    Technical Details:
    The vulnerable code exists in Flash.ocx, which embodies the code
    responsible for playing back SWF files. One function maintains a large,
    256-element table of function pointers on the stack, and uses a frame
    type identifier read from the SWF file as an index into the array,
    without enforcing the array boundaries. The following disassembly
    depicts the affected code:

        .text:1002714F mov eax, [esi+0CA4h] ; type number
        .text:10027155 mov ecx, [esi+94h] ; base of table
        .text:1002715B lea eax, [ecx+eax*8] ; get element address
        .text:1002715E mov ecx, [eax] ;

    Although the index is not validated, its value is elsewhere restricted
    to be at most 0x8000, so the attacker can cause a function pointer to be
    retrieved from memory up to roughly 64KB after the base of the table on
    the stack. Typically this range will include heap memory, so by
    planting specific data on the heap, the attacker can very easily control
    the exact value of the function pointer. Reliable exploitation using
    this technique within Internet Explorer has been demonstrated by eEye
    Digital Security.

    Retina Network Security Scanner has been updated to identify this
    Blink - Endpoint Vulnerability Prevention - protects from this

    Vendor Status:
    Macromedia has addressed this issue in the following security bulletin;

    This vulnerability has been assigned the CVE identifier CAN-2005-2628
    and OSVDB ID 18825.

    Thanks Derek and and eEye guys help me wrote this advisory. Greeting
    xfocus guys and venustech lab guys.

    Fang Xing

    Copyright (c) 1998-2005 eEye Digital Security Permission is hereby
    granted for the redistribution of this alert electronically. It is not
    to be edited in any way without express consent of eEye. If you wish to
    reprint the whole or any part of this alert in any other medium
    excluding electronic medium, please email alert@eEye.com for permission.

    The information within this paper may change without notice. Use of this
    information constitutes acceptance for use in an AS IS condition. There
    are no warranties, implied or express, with regard to this information.
    In no event shall the author be liable for any direct or indirect
    damages whatsoever arising out of or in connection with the use or
    spread of this information. Any use of this information is at the user's
    own risk.

  • Next message: Advisories_at_eeye.com: "[VulnWatch] [EEYEB-20050901] Windows Metafile SetPalette Entries Heap OVerflow Vulnerability (Graphics Rendering Engine Vulnerability)"