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Old 02-10-2011, 02:47
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Fyyre Fyyre is offline
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This code is intended to crash Ollydbg, or cause a silent exit ?


Originally Posted by arlequim View Post
I see you are really interested on this subject, here is a little tricks for OllyDbg 1.10:

;bye OllyDbg 1.10 :))
byeolly qword -1
word 403Dh
fld tbyte ptr ds:[byeolly] 
end start
Dunno if it works, let me know. Bye!
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Old 02-10-2011, 06:29
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arlequim arlequim is offline
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Originally Posted by Fyyre View Post
This code is intended to crash Ollydbg, or cause a silent exit ?

Unfortunately i can't reply you atm, try yourself as it ain't dangerous code...
If i gather other anti debug codes, i will post then on this thread, be sure. Bye!
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Old 02-10-2011, 13:13
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fld tbyte ptr ds:[byeolly]
this bug is pretty old, strongod fix fpu-bug will fix it, also there're was patch for it
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Old 08-31-2011, 14:27
Evilcry Evilcry is offline
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Searched on the forum to not duplicate post, last reference was on previous version, so here:

OllyDbg plugin Stealth64 1.3

Anti Anti and compatibility plugin for Olly 1.10 running on Vista x64.

I made this little plugin to make unpacking on Vista x64 a bit more bearable

It has most of the know anti-anti and makes an effort to make Olly behave like it should on regular x86 machines.
Next to this I implemented my own version of the OllyBone 'Break On Execute' making unpacking some simple packers a lot easier.


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Old 11-15-2011, 05:24
qkumba qkumba is offline
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The FPU bug causes OllyDbg to crash when disassembling that part of the code.
It's caused by using the wrong mask, so the exception is not hidden.
Most of the patches don't fix the problem (just needs to change the mask) - they change the instruction or do other silly things.
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