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Figure 6-5: Graph view of the vulnerable code path in IDA Pro, part 2Here’s some pseudo C code of that memcpy() call:memcpy ([EAX+0x18], ESI + 4, 0x21a * 4);Or, in more abstract terms:memcpy (user_controlled_address, user_controlled_data, 0x868);It is therefore possible to write 0x868 bytes (0x21a * 4 bytes, as therep movsd instruction copies DWORDs from one location to another)of user-controllable data to an arbitrary user-controlled address ineither user or kernel space. Nice!The anatomy of the bug, diagrammed in Figure 6-6, is as follows:1. An IOCTL request (0xB2D60030) is sent to the kernel driverAavmker4.sys using the AavmKer4 device.2. The driver code checks whether the IOCTL input data lengthequals the value 0x878. If so, proceed to step 3.102 Chapter 6
Aavmker4.sys(2)input data length == 0x878?Kernel Space(3)Does the user input contain the values0xD0DEAD07 and 0x10BAD0BA?\Device\AavmKer4(4)IOCTL request:0xB2D60030(1)User Spacememcpy (user_controlled_address,user_controlled_value, 0x868)(5)Memory Corruption!Figure 6-6: Overview of the vulnerability from IOCTL request to memory corruption3. The driver checks whether the user-controlled IOCTL input datacontains the values 0xD0DEAD07 and 0x10BAD0BA. If so, proceed tostep 4.4. The erroneous memcpy() call is executed.5. The memory is corrupted.6.2 ExploitationTo gain control of EIP, I first had to find a suitable target address tooverwrite. While searching through the IOCTL dispatch routine, Ifound two places where a function pointer is called:[..].text:00010D8F push 2 ; _DWORD.text:00010D91 push 1 ; _DWORD.text:00010D93 push 1 ; _DWORD.text:00010D95 push dword ptr [eax] ; _DWORD.text:00010D97 call KeGetCurrentThread.text:00010D9C push eax ; _DWORD.text:00010D9D call dword_12460 ; the function pointer is called.text:00010DA3 mov [ebx+18h], eax.text:00010DA6 jmp loc_10F04[..].text:00010DB6 push 2 ; _DWORD.text:00010DB8 push 1 ; _DWORDOne Kernel to Rule Them All 103
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A Bug Hunter’s Diary. Copyright
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Chapter 3: Escape from the WWW Zone
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B.2 The Windows Debugger (WinDbg) .
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IntroductionWelcome to A Bug Hunter
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1Bug HuntingBug hunting is the proc
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After I’ve found a bug, I want to
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Table 1-1: Debuggers Used in This B
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2Back to the ’90sSunday, October
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16361637 /* clear the SEQ table */1
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If a TiVo file is loaded by VLC, th
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Get the →vulnerableWindows versio
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EIP = 41414141 . . . Mission EIP co
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NoteTo configure Process Explorer t
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See the following excerpt from the
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3. Immunity Debugger is a great Win
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NoteInput/output controls (IOCTLs)
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msgbb_datapdatabb_rptrdb_basedatabu
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8180 /*8181 * Null terminate the st
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26736 /*26737 * SIOC[GS]TUNPARAM ap
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19165 * are also rejected as they i
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01 #include 02 #include 03 #include
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fffffe8000f7e4b0 unix:die+da ()ffff
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zero pagenot mappedzero pageis mapp
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gaining full control over EIP/RIP a
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112 return 1;113 }114115 printf ("O
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solaris$ isainfo -b64I then compile
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ip_output+0x10()ip_wput+0x37()putne
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Notes1. The source code of OpenSola
Page 66 and 67: 4.1 Vulnerability DiscoveryTo find
Page 68 and 69: 167 if (current_track + 1 > fourxm-
Page 71 and 72: Step 1: Find a Sample 4X Movie File
Page 73 and 74: Next, I modified the values of trac
Page 75 and 76: Table 4-2: List of the Assembler In
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Page 79 and 80: linux$ gdb -q ./ffmpeg_g(gdb) run -
Page 81 and 82: (UINT_MAX / sizeof(AudioTrack) - 1)
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Page 85 and 86: 5Browse and You’re OwnedSunday, A
Page 87 and 88: {SWI.ClassId_q.ClassId clsid = new
Page 89 and 90: 27 except KeyboardInterrupt:28 prin
Page 91 and 92: Figure 5-4: Defining a breakpoint a
Page 93 and 94: Figure 5-7: User-controlled argumen
Page 95 and 96: Next, I tried to retrieve the size
Page 97 and 98: 05 06 arg = String(232, "A") + Stri
Page 99: iDefense VCPnotifiedVulnerability d
Page 102 and 103: 6.1 Vulnerability DiscoveryI used t
Page 104 and 105: Step 3: Check the Device Security S
Page 106 and 107: Below, the elements of the MajorFun
Page 108 and 109: At address .text:00010748, a pointe
Page 110 and 111: [..][..]//// Current stack location
Page 112 and 113: The transfer type is specified usin
Page 114 and 115: If the requested IOCTL code matches
Page 118 and 119: .text:00010DBA push 1 ; _DWORD.text
Page 120 and 121: 99 // .text:00010DEF cmp dword ptr
Page 122 and 123: nt!RtlpBreakWithStatusInstruction:8
Page 124 and 125: After I gained control over EIP, I
Page 127 and 128: 7A Bug Older Than 4.4BSDSaturday, M
Page 129 and 130: Here are some examples:Source code
Page 131 and 132: 1094 return (ENXIO);1095 if (t != t
Page 133 and 134: 4. The assumed address of l_open()
Page 135 and 136: osx$ cat /Library/Logs/panic.logSat
Page 137 and 138: Back on the Linux host, I started t
Page 139 and 140: 0x35574c, the value is used to calc
Page 141 and 142: 48 define search_memloc49 set $max_
Page 143 and 144: As the debugger output shows, the E
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Page 148 and 149: I performed the following steps whe
Page 150 and 151: I then began fuzzing files of the A
Page 152 and 153: Figure 8-1: Playing the unmodifiedA
Page 154 and 155: • Line 40 copies the current proc
Page 156 and 157: As the debugger output shows, media
Page 158 and 159: The manipulated byte (0xff) that ca
Page 160 and 161: (gdb) x/12x 0x1301bfc0x1301bfc: 0x0
Page 162 and 163: ApplenotifiedApple confirmsthe vuln
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eip 0x43434343 0x43434343eflags 0x1
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The access violation is caused when
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is less than 12. If it is, the stri
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The program in Listing A-4 calls th
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0x080483f3 : mov DWORD PTR [esp+0x4
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BDebuggingThis appendix contains in
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Information CommandsCommandDescript
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Information CommandsCommandrkbu add
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Figure B-3: Configuration settings
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Figure B-6: Attaching the kernel de
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Other CommandsCommandset disassembl
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linux# pwd/home/tk/gdb-292/srclinux
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Notes1. See the Solaris Modular Deb
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The many mitigation techniques coul
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Figure C-1: DEP and ASLR status sho
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08 p[0] = 0x41414141;09 printf (“
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ConclusionIn case of a buffer overf
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zonecfg:wwwzone> set autoboot=truez
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Notes1. See Rob King, “New Leopar
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COMRaider, 72coordinated disclosure
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Rreadelf, 161RELRO, 67-69, 183-186r
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A Bug Hunter’s Diary is set in Ne
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