Reverse engineered code for Microsoft's WARBIRD obfuscator
Microsoft developed Warbird to obfuscate different system components, mostly relating to DRM and licensing.
Warbird code has even been integrated into the kernel to obfuscate components (ci
, peauth
, clipsp
, etc).
Warbird can support different forms of code obfuscation like:
- virtual machine obfuscation
- section encryption/packing (labeled
PAGEwx
sections which are excluded from PatchGuard) - constant obfuscation
- runtime code execution on the heap (
SystemControlFlowTransition
info class forNtQuerySystemInformation
system call)
Some system images that are publicly known to use Warbird are:
ci.dll
clipsp.sys
peauth.sys
ntoskrnl.exe
ClipSVC.dll
ClipUp.exe
Windows.Media.Protection.PlayReady.dll
GenValObj.exe
ManageCI.dll
There are other images that make calls to NtQuerySystemInformation
passing the SystemPolicyInformation
info class that rely on the Warbird Feistel cipher to encrypt/decrypt parameters.
The call stack of those calls generally look like:
nt!SpCall2ServerInternal
-> nt!g_kernelCallbacks
-> clipsp.sys!ClipSp*
.
More information can be found on that here.
WarbirdRuntime::CTermination
WarbirdRuntime::CMemoryAllocator::CBlock
WarbirdRuntime::CEncryption
WarbirdRuntime::CPrivateRelocationsTable
WarbirdRuntime::CHeapExecution
WarbirdRuntime::AutoEnableDynamicCodeGen
WarbirdRuntime::CUtil
WarbirdRuntime::CRWLock
WarbirdRuntime::CMemoryProtectionChangeHelper
WarbirdRuntime::WarbirdRuntime__HEAP_EXECUTION_CALL_ARGUMENTS
WarbirdRuntime::WarbirdRuntime__HEAP_EXECUTION_CONDITIONAL_BRANCH_ARGUMENTS
WarbirdRuntime::ENCRYPTED_SEGMENT_DATA_CONST
WarbirdRuntime::ENCRYPTED_SEGMENT_DATA_READ_WRITE
WarbirdRuntime::RuntimeInit
WarbirdRuntime::NewEntryMain
The project cannot be used as-is and is merely intended to be used for educational purposes to further public understanding.
Warbird cannot be integrated into personal projects since the actual runtime dlls are not present.
A custom Warbird obfuscator toolset could be partially integrated by passing the /wbrddll:
MSVC compiler flag and exporting the GetObfuscator
and CreateObfuscator2
routines.
UPDATE: As of 6/11/24, it is possible to integrate the leaked warbird.dll
to build applications.
The project could be loosely modified to support calls to NtQuerySystemInformation
with the SystemPolicyInformation
class but you would have to reimplement the cipher, get the encryption/decryption keys, etc... :)