Checking Installed Software

Created the Monday 11 March 2019. Updated 3 months ago.

By detecting the presence of certain software and tools commonly used in sandbox environments, such as Python interpreters, tracing utilities, debugging tools, and virtual machine software like VMware, it is possible to infer the existence of a sandbox.

This inference is based on the premise that such tools are often found in sandbox setups used for dynamic malware analysis but are less common in regular user environments.

Technique Identifier

U1314

Technique Tags

installed software sandbox

Featured Windows API's

Below, you will find a list of the most commonly used Windows API's that are currently utilized by malware authors for current evasion technique. This list is meant to provide an overview of the API's that are commonly used for this purpose. If there are any API's that you feel should be included on this list, please do not hesitate to contact us. We will be happy to update the list and provide any additional information or documentation that may be helpful.

Code Snippets

Description

This code snippet will browse the registry to check installed software.

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

bool EnumInstalledSoftware(void)
{
    HKEY hUninstKey = NULL;
    HKEY hAppKey = NULL;
    WCHAR sAppKeyName[1024];
    WCHAR sSubKey[1024];
    WCHAR sDisplayName[1024];
    WCHAR *sRoot = L"SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Uninstall";
    long lResult = ERROR_SUCCESS;
    DWORD dwType = KEY_ALL_ACCESS;
    DWORD dwBufferSize = 0;

    if(RegOpenKeyExW(HKEY_LOCAL_MACHINE, sRoot, 0, KEY_READ, &hUninstKey) != ERROR_SUCCESS)
    {
        return false;
    }

    for(DWORD dwIndex = 0; lResult == ERROR_SUCCESS; dwIndex++)
    {
        dwBufferSize = sizeof(sAppKeyName);
        if((lResult = RegEnumKeyExW(hUninstKey, dwIndex, sAppKeyName,
            &dwBufferSize, NULL, NULL, NULL, NULL)) == ERROR_SUCCESS)
        {
            //printf(sSubKey, L"%s\\%s", sRoot, sAppKeyName);
            if(RegOpenKeyExW(HKEY_LOCAL_MACHINE, sSubKey, 0, KEY_READ, &hAppKey) != ERROR_SUCCESS)
            {
                RegCloseKey(hAppKey);
                RegCloseKey(hUninstKey);
                return false;
            }

            dwBufferSize = sizeof(sDisplayName);
            if(RegQueryValueExW(hAppKey, L"DisplayName", NULL,
                &dwType, (unsigned char*)sDisplayName, &dwBufferSize) == ERROR_SUCCESS)
            {
                wprintf(L"%s\n", sDisplayName);
            }

            RegCloseKey(hAppKey);
        }
    }

    RegCloseKey(hUninstKey);

    return true;
}

Detection Rules

                                    rule check_installed_software {

  meta:
    author = "RussianPanda"
    date = "1/14/2024"
    reference = "https://unprotect.it/technique/checking-installed-software/"
    hash = "db44d4cd1ea8142790a6b26880b41ee23de5db5c2a63afb9ee54585882f1aa07"

  strings:
    $d1 = "DisplayVersion"
    $u1 = "SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Uninstall"
    $reg = "RegOpenKeyExA"
    $h = {68 (01|02) 00 00 80}

  condition:
    uint16(0) == 0x5A4D
    and for any i in (1..#u1) : ($d1 in (@u1[i] - 200..@u1[i] + 200))
    and $reg and $h

}

Contributors

RussianPanda

Additional Resources

External Links

The resources provided below are associated links that will give you even more detailed information and research on current evasion technique. It is important to note that, while these resources may be helpful, it is important to exercise caution when following external links. As always, be careful when clicking on links from unknown sources, as they may lead to malicious content.