klezvirus/syswhispers3SysWhispers on Steroids - AV/EDR evasion via direct system calls.
SysWhispers helps with evasion by generating header/ASM files implants can use to make direct system calls.
Come hang out on Discord!
The reason for SysWhispers3 to be a standalone version are many, but the most important are:
The usage is pretty similar to SysWhispers2, with the following exceptions:
A better explanation of these features are better outlined i the blog post SysWhispers is dead, long live SysWhispers!
Security products, such as AVs and EDRs, usually place hooks in user-mode API functions to analyse a program execution flow, in order to detect potentially malicious activities.
SysWhispers2 is a tool designed to generate header/ASM pairs for any system call in the core kernel image
(ntoskrnl.exe), which can then be integrated and called directly from C/C++ code, evading user-lands hooks.
The tool, however, generates some patters which can be included in signatures, or behaviour which can be detected at runtime.
SysWhispers3 is built on top of SysWhispers2, and integrates some helpful features to bypass these forms of detection.
C:\> git clone https://github.com/klezVirus/SysWhispers3.git
C:\> cd SysWhispers3
C:\> python .\syswhispers.py --help
The help shows all the available commands and features of the tool:
C:\>python syswhispers.py -h
usage: syswhispers.py [-h] [-p PRESET] [-a {x86,x64}] [-m {embedded,egg_hunter,jumper,jumper_randomized}] [-f FUNCTIONS] -o OUT_FILE [--int2eh] [--wow64] [-v] [-d]
SysWhispers3 - SysWhispers on steroids
optional arguments:
-h, --help show this help message and exit
-p PRESET, --preset PRESET
Preset ("all", "common")
-a {x86,x64}, --arch {x86,x64}
Architecture
-c {msvc,mingw,all}, --compiler {msvc,mingw,all}
Compiler
-m {embedded,egg_hunter,jumper,jumper_randomized}, --method {embedded,egg_hunter,jumper,jumper_randomized}
Syscall recovery method
-f FUNCTIONS, --functions FUNCTIONS
Comma-separated functions
-o OUT_FILE, --out-file OUT_FILE
Output basename (w/o extension)
--int2eh Use the old `int 2eh` instruction in place of `syscall`
--wow64 Use Wow64 to run x86 on x64 (only usable with x86 architecture)
-v, --verbose Enable debug output
-d, --debug Enable syscall debug (insert software breakpoint)
# Export all functions with compatibility for all supported Windows versions (see example-output/).
py .\syswhispers.py --preset all -o syscalls_all
# Export just the common functions (see below for list).
py .\syswhispers.py --preset common -o syscalls_common
# Export NtProtectVirtualMemory and NtWriteVirtualMemory with compatibility for all versions.
py .\syswhispers.py --functions NtProtectVirtualMemory,NtWriteVirtualMemory -o syscalls_mem
# Normal SysWhispers, 32-bits mode
py .\syswhispers.py --preset all -o syscalls_all -m jumper --arch x86
# Normal SysWhispers, using WOW64 in 32-bits mode (only specific functions)
py .\syswhispers.py --functions NtProtectVirtualMemory,NtWriteVirtualMemory -o syscalls_mem --arch x86 --wow64
# Egg-Hunting SysWhispers, to bypass the "mark of the sycall" (common function)
py .\syswhispers.py --preset common -o syscalls_common -m egg_hunter
# Jumping/Jumping Randomized SysWhispers, to bypass dynamic RIP validation (all functions) using MinGW as the compiler
py .\syswhispers.py --preset all -o syscalls_all -m jumper -c mingw
PS C:\Projects\SysWhispers2> py .\syswhispers.py --preset common --out-file temp\syscalls_common -v
. ,--.
,-. . . ,-. . , , |-. o ,-. ,-. ,-. ,-. ,-. __/
`-. | | `-. |/|/ | | | `-. | | |-' | `-. . \
`-' `-| `-' ' ' ' ' ' `-' |-' `-' ' `-' '''
/| | @Jackson_T
`-' ' @modexpblog, 2021
Edits by @klezVirus, 2022
SysWhispers3: Why call the kernel when you can whisper?
Common functions selected.
Complete! Files written to:
temp\syscalls_common.h
temp\syscalls_common.c
temp\syscalls_common_.asm
Press a key to continue...
Makefile for 64 bits:
Makefile.msvc
OPTIONS = -Zp8 -c -nologo -Gy -Os -O1 -GR- -EHa -Oi -GS-
LIBS = libvcruntime.lib libcmt.lib ucrt.lib kernel32.lib
program:
ML64 /c syscalls-asm.x64.asm /link /NODEFAULTLIB /RELEASE /MACHINE:X64
cl.exe $(OPTIONS) syscalls.c program.c
link.exe /OUT:program.x64.exe -nologo $(LIBS) /MACHINE:X64 -subsystem:console -nodefaultlib syscalls-asm.x64.obj syscalls.obj program.obj
Makefile for 32 bits:
Makefile.msvc
OPTIONS = -Zp8 -c -nologo -Gy -Os -O1 -GR- -EHa -Oi -GS-
LIBS = libvcruntime.lib libcmt.lib ucrt.lib kernel32.lib
program:
ML /c syscalls-asm.x86.asm /link /NODEFAULTLIB /RELEASE /MACHINE:X86
cl.exe $(OPTIONS) syscalls.c program.c
link.exe /OUT:program.x86.exe -nologo $(LIBS) /MACHINE:X86 -subsystem:console -nodefaultlib syscalls-asm.x86.obj syscalls.obj program.obj
Compile with nmake:
nmake -f Makefile.msvc
Makefile for both 64 and 32 bits:
Makefile.mingw
CC_x64 := x86_64-w64-mingw32-gcc
CC_x86 := i686-w64-mingw32-gcc
OPTIONS := -masm=intel -Wall
program:
$(CC_x64) syscalls.c program.c -o program.x64.exe $(OPTIONS)
$(CC_x86) syscalls.c program.c -o program.x86.exe $(OPTIONS)
Compile with make:
make -f Makefile.mingw
win32k.sys) are not supported.syscalls.h have already been defined.
--preset all is rarely necessary).syscalls.h.--verbose, it is possible to enable troubleshooting output during code generation.--debug, the tool will insert a software breakpoint in the syscall stub, to ease the debugging in WinDbg.error A2084:constant value too large during compilation, regenerates the stubs.Developed by @Jackson_T and @modexpblog, but builds upon the work of many others:
As the original, this project is also licensed under the Apache License 2.0.