moyix

The ffast and the Furious

This is a small and admittedly contrived demo showing how some weird but safe code could become vulnerable if run in an environment where some shared library has changed the FPU's FTZ/DAZ bits to force denormals to zero.

To run it:

# Create an empty file
$ touch gofast.c      

muff-in

Assembly Language / Reversing / Malware Analysis / Game Hacking -resources

⭐Assembly Language

Modern x64 Assembly

https://www.youtube.com/playlist?list=PLKK11Ligqitg9MOX3-0tFT1Rmh3uJp7kA

psifertex

Welcome to Jordan's grab-bag of common Binary Ninja Snippets.

These snippest are meant to run with the Binary Ninja Snippets Plugin
(http://github.com/Vector35/snippets) though they can all also be pasted
directly into the python console or turned into stand-alone plugins if needed.

To install the entire collection at once, just install the Snippets plugin via
the plugin manager (CMD/CTL-SHIFT-M), confirm the Snippet Editor works
(Tool/Snippets/Snippet Editor), and unzip this bundle (Download ZIP above) into
your Snippets folder.

coolreader18

class E(BaseException):
    def __new__(cls, *args, **kwargs):
        return cls
def a(): yield
a().throw(E)

MattPD

Program Analysis Resources

(draft; work in progress)

See also:

• Compilers
  • correctness
• Program analysis:
• Dynamic analysis - instrumentation, translation, sanitizers

Jinmo

Usage

In IDAPython,

execfile('<path>/cxxparser.py')
parse_file('<path>/a.cpp',[r'-I<path>\LuaJIT-2.0.5\src', '-D__NT__', '-D__X64__', '-D__EA64__'])
parse_file('<path>/malloc.c',['-target=x86_64-linux-gnu'])

yifanlu

williballenthin

manual import resolution

example from 0f5d5d07c6533bc6d991836ce79daaa1:

_0:00F20012 33 D2                   xor     edx, edx
_0:00F20014 64 8B 52 30             mov     edx, fs:[edx+30h] // TEB->PEB
_0:00F20018 8B 52 0C                mov     edx, [edx+0Ch]    // PEB->LDR_DATA
_0:00F2001B 8B 52 14                mov     edx, [edx+14h]    // LDR_DATA->InMemoryOrderLinks (_LDR_DATA_TABLE_ENTRY)
                                                              // alt: 0xC: InLoadOrderLinks
 // alt: 0x1C: InInitializationOrderLinks

pzread

天衣無縫 ~ Fantastic Seamless Textile ~

When executing a ELF binary, Linux kernel will pass the memory address of PHDR(program header) to userspace by AT_PHDR entry of AUXV.

ld.so interpreter will parse the PHDR structure at memory addressAT_PHDR and resolve more ELF structures, such as dynamic section.

But Linux kernel wrongly calculate the PHDR address in memory.

NEW_AUX_ENT(AT_PHDR, load_addr + exec->e_phoff);

rygorous

Why do compilers even bother with exploiting undefinedness signed overflow? And what are those
mysterious cases where it helps?

A lot of people (myself included) are against transforms that aggressively exploit undefined behavior, but
I think it's useful to know what compiler writers are accomplishing by this.

TL;DR: C doesn't work very well if int!=register width, but (for backwards compat) int is 32-bit on all
major 64-bit targets, and this causes quite hairy problems for code generation and optimization in some
fairly common cases. The signed overflow UB exploitation is an attempt to work around this.