Checking Memory Size

Created the Monday 11 March 2019. Updated 1 year, 1 month ago.

Most modern user machines have at least 4GB of memory. Malware programs can detect whether they are running in a sandbox environment by checking the available memory size. If the available memory size is less than 4GB, it is likely that the program is running in a sandbox.

Technique Identifiers

U1313 B0009.014

Technique Tags

memory malware sandbox available memory size.

Code Snippets

Description

This code uses the MEMORYSTATUSEX structure and the GlobalMemoryStatusEx function from the Windows API to retrieve information about the system's memory status, including the total physical memory and the available physical memory.

#include <windows.h>
#include <iostream>

int main() {
    MEMORYSTATUSEX memInfo;
    memInfo.dwLength = sizeof(MEMORYSTATUSEX);
    GlobalMemoryStatusEx(&memInfo);

    std::cout << "Total physical memory: " << memInfo.ullTotalPhys / 1024 / 1024 << " MB\n";
    std::cout << "Available physical memory: " << memInfo.ullAvailPhys / 1024 / 1024 << " MB\n";

    return 0;
}

About Author Open Snippet

Author: Thomas Roccia (fr0gger) / Target Platform: Windows

package main

import (
	"unsafe"
	"syscall"
	"fmt"
)

var (
	kernel_32               = syscall.MustLoadDLL("kernel32.dll")
	globalMemoryStatusEx, _ = kernel_32.FindProc("GlobalMemoryStatusEx")
)

type memStatusEx struct {
	dwLength     uint32
	dwMemoryLoad uint32
	ullTotalPhys uint64
	unused       [6]uint64
}

func evadeSystemMemory() () {
	msx := &memStatusEx{dwLength: 64}
	r, _, _ := globalMemoryStatusEx.Call(uintptr(unsafe.Pointer(msx)))
	if r == 0 {
		fmt.Println("Error getting memory status")
	}

	var maxMemory float64 = 2.0
	var system_memory = float64(msx.ullTotalPhys/1024/1024) / 1024

	if system_memory <= maxMemory {
		fmt.Println("Sandbox detected")
	} else {
		fmt.Println("Sandbox not detected")
	}
}

func main() {
	evadeSystemMemory()
}

About Author Open Snippet

Author: Edode / Target Platform: Windows

Additional Resources

External Links

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