What is assistant_package?

assistant_package is part of Opera browser assistant according to the assistant_package version information.

assistant_package's description is "Opera installer SFX"

assistant_package is digitally signed by Opera Software AS.

assistant_package is usually located in the 'c:\$Recycle.Bin\S-1-5-21-3018067107-4063884592-1655906936-1001\$RE9O2EH\71.0.3770.171\' folder.

None of the anti-virus scanners at VirusTotal reports anything malicious about assistant_package.

If you have additional information about the file, please share it with the FreeFixer users by posting a comment at the bottom of this page.

VirusTotal report

None of the 71 anti-virus programs at VirusTotal detected the assistant_package file.

Sandbox Report

The following information was gathered by executing the file inside Cuckoo Sandbox.

Summary

Successfully executed process in sandbox.

Summary

{
    "file_created": [
        "C:\\Users\\cuck\\AppData\\Local\\Temp\\assistant_installer.exe",
        "C:\\Users\\cuck\\AppData\\Local\\Temp\\files_list",
        "C:\\Users\\cuck\\AppData\\Local\\Temp\\browser_assistant.exe"
    ],
    "directory_created": [
        "C:\\Users\\cuck\\AppData\\Local\\Temp"
    ],
    "dll_loaded": [
        "kernel32",
        "kernel32.dll",
        "UxTheme.dll",
        "dwmapi.dll",
        "comctl32.dll",
        "C:\\Windows\\system32\\uxtheme.dll"
    ],
    "file_opened": [
        "C:\\Users\\cuck\\AppData\\Local\\Temp\\04ee0d96b396798f19bda2adfc22e90165b06f017e4123b61b5f68d52c70db01.bin",
        "C:\\Windows\\Globalization\\Sorting\\sortdefault.nls"
    ],
    "file_written": [
        "C:\\Users\\cuck\\AppData\\Local\\Temp\\assistant_installer.exe",
        "C:\\Users\\cuck\\AppData\\Local\\Temp\\files_list",
        "C:\\Users\\cuck\\AppData\\Local\\Temp\\browser_assistant.exe"
    ],
    "file_exists": [
        "C:\\Users\\cuck\\AppData\\Local\\Temp\\assistant_installer.exe",
        "C:\\Users\\cuck\\AppData\\Local\\Temp\\files_list",
        "C:\\Users\\cuck\\AppData\\Local\\Temp\\browser_assistant.exe",
        "C:\\Users\\cuck\\AppData\\Local\\Temp"
    ],
    "file_read": [
        "C:\\Users\\cuck\\AppData\\Local\\Temp\\04ee0d96b396798f19bda2adfc22e90165b06f017e4123b61b5f68d52c70db01.bin"
    ],
    "regkey_read": [
        "HKEY_LOCAL_MACHINE\\SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\GRE_Initialize\\DisableMetaFiles",
        "HKEY_LOCAL_MACHINE\\SYSTEM\\ControlSet001\\Control\\Nls\\CustomLocale\\en-US",
        "HKEY_LOCAL_MACHINE\\SYSTEM\\ControlSet001\\Control\\Nls\\ExtendedLocale\\en-US"
    ]
}

Dropped

[
    {
        "yara": [],
        "sha1": "f8d0c3b21766999004ffcd0ffe7c63cce23e4f64",
        "name": "574c22c4371aa928_files_list",
        "filepath": "C:\\Users\\cuck\\AppData\\Local\\Temp\\files_list",
        "type": "ASCII text, with CRLF line terminators",
        "sha256": "574c22c4371aa928ec7bada51b8f9b8751520883cd84da0d524e5eb888a362f0",
        "urls": [],
        "crc32": "5A3799B7",
        "path": "\/home\/hpuser\/.cuckoo\/storage\/analyses\/9739\/files\/574c22c4371aa928_files_list",
        "ssdeep": null,
        "size": 46,
        "sha512": "dfd8b7e00edfa47c47167de4a7e7e5707a48de0ad651c35c79b90035ae6babe677557e9be4b1703b990a2b6c83b7dee3f4a6747c4857e0a2d3b5b81767b52c42",
        "pids": [
            2740
        ],
        "md5": "4cf654738dc993493ab53507ddd47c0c"
    },
    {
        "yara": [],
        "sha1": "e946b6a2053e6c85002c569ca8cbdacca3d6fbef",
        "name": "882d11a5d9f605bb_browser_assistant.exe",
        "filepath": "C:\\Users\\cuck\\AppData\\Local\\Temp\\browser_assistant.exe",
        "type": "PE32+ executable (GUI) x86-64, for MS Windows",
        "sha256": "882d11a5d9f605bbe27168cd2aa302df52cfff12c792234d32a7c54cd976ca2a",
        "urls": [
            "http:\/\/crl3.digicert.com\/DigiCertHighAssuranceEVRootCA.crl0",
            "http:\/\/crl4.digicert.com\/EVCodeSigningSHA2-g1.crl0K",
            "http:\/\/cacerts.digicert.com\/DigiCertAssuredIDRootCA.crt0",
            "http:\/\/ocsp.digicert.com0C",
            "http:\/\/crl3.digicert.com\/EVCodeSigningSHA2-g1.crl07",
            "https:\/\/curl.haxx.se\/docs\/http-cookies.html",
            "https:\/\/crashstats-collector.opera.com\/collector\/submit",
            "https:\/\/crashpad.chromium.org\/bug\/new",
            "http:\/\/crl4.digicert.com\/sha2-assured-ts.crl0",
            "http:\/\/cacerts.digicert.com\/DigiCertSHA2AssuredIDTimestampingCA.crt0",
            "http:\/\/cacerts.digicert.com\/DigiCertHighAssuranceEVRootCA.crt0",
            "https:\/\/autoupdate.geo.opera.com\/",
            "http:\/\/ocsp.digicert.com0O",
            "http:\/\/crl3.digicert.com\/DigiCertAssuredIDRootCA.crl0P",
            "http:\/\/ocsp.digicert.com0I",
            "http:\/\/ocsp.digicert.com0H",
            "http:\/\/crl4.digicert.com\/DigiCertHighAssuranceEVRootCA.crl0",
            "http:\/\/crl3.digicert.com\/sha2-assured-ts.crl02",
            "https:\/\/browser-notifications.opera.com\/api\/v1\/",
            "http:\/\/www.opera.com0",
            "https:\/\/crashpad.chromium.org\/",
            "http:\/\/cacerts.digicert.com\/DigiCertEVCodeSigningCA-SHA2.crt0",
            "http:\/\/crl4.digicert.com\/DigiCertAssuredIDRootCA.crl0:",
            "https:\/\/www.digicert.com\/CPS0",
            "http:\/\/www.digicert.com\/ssl-cps-repository.htm0"
        ],
        "crc32": "79936D9D",
        "path": "\/home\/hpuser\/.cuckoo\/storage\/analyses\/9739\/files\/882d11a5d9f605bb_browser_assistant.exe",
        "ssdeep": null,
        "size": 3545112,
        "sha512": "9e175762e7e3fb80d16d5c4b24bd4f137f45b3391a71e7147b7e4584b978593e8d2f59baa993794dc74fab27d505c619d2f3931b06cdb6cf784f0cad8102f64b",
        "pids": [
            2740
        ],
        "md5": "eab69d7150c02d255fa9780f25aa2f3c"
    },
    {
        "yara": [],
        "sha1": "8ca42745fd62860fca5d15cc20ad0fda863a4385",
        "name": "153e4d59f96021d5_assistant_installer.exe",
        "filepath": "C:\\Users\\cuck\\AppData\\Local\\Temp\\assistant_installer.exe",
        "type": "PE32+ executable (GUI) x86-64, for MS Windows",
        "sha256": "153e4d59f96021d5fc98e93560a19a8b91ce8926b0ad97bc34409169f35853a5",
        "urls": [
            "http:\/\/crl3.digicert.com\/DigiCertHighAssuranceEVRootCA.crl0",
            "http:\/\/crl4.digicert.com\/EVCodeSigningSHA2-g1.crl0K",
            "http:\/\/cacerts.digicert.com\/DigiCertAssuredIDRootCA.crt0",
            "http:\/\/ocsp.digicert.com0C",
            "http:\/\/crl3.digicert.com\/EVCodeSigningSHA2-g1.crl07",
            "http:\/\/crl4.digicert.com\/DigiCertHighAssuranceEVRootCA.crl0",
            "https:\/\/crashstats-collector.opera.com\/collector\/submit",
            "https:\/\/crashpad.chromium.org\/bug\/new",
            "http:\/\/crl4.digicert.com\/sha2-assured-ts.crl0",
            "http:\/\/cacerts.digicert.com\/DigiCertSHA2AssuredIDTimestampingCA.crt0",
            "http:\/\/cacerts.digicert.com\/DigiCertHighAssuranceEVRootCA.crt0",
            "https:\/\/autoupdate.geo.opera.com\/",
            "http:\/\/ocsp.digicert.com0O",
            "http:\/\/crl3.digicert.com\/DigiCertAssuredIDRootCA.crl0P",
            "http:\/\/ocsp.digicert.com0I",
            "http:\/\/ocsp.digicert.com0H",
            "http:\/\/crl3.digicert.com\/sha2-assured-ts.crl02",
            "http:\/\/www.opera.com0",
            "https:\/\/crashpad.chromium.org\/",
            "http:\/\/cacerts.digicert.com\/DigiCertEVCodeSigningCA-SHA2.crt0",
            "http:\/\/crl4.digicert.com\/DigiCertAssuredIDRootCA.crl0:",
            "https:\/\/www.digicert.com\/CPS0",
            "http:\/\/www.digicert.com\/ssl-cps-repository.htm0"
        ],
        "crc32": "191EC822",
        "path": "\/home\/hpuser\/.cuckoo\/storage\/analyses\/9739\/files\/153e4d59f96021d5_assistant_installer.exe",
        "ssdeep": null,
        "size": 2033176,
        "sha512": "bfed003222d9e429e5a7d6bd166d5087ad6d06e371e38826a48778b1d07518e6123516433d593c3a873ae0e66d6f276c6396e667a7bf3f96c48bc7bd2671f972",
        "pids": [
            2740
        ],
        "md5": "bb34ca5a0a96b73af4410eee2b628529"
    }
]

Generic

[
    {
        "process_path": "C:\\Users\\cuck\\AppData\\Local\\Temp\\04ee0d96b396798f19bda2adfc22e90165b06f017e4123b61b5f68d52c70db01.bin",
        "process_name": "04ee0d96b396798f19bda2adfc22e90165b06f017e4123b61b5f68d52c70db01.bin",
        "pid": 2740,
        "summary": {
            "file_created": [
                "C:\\Users\\cuck\\AppData\\Local\\Temp\\assistant_installer.exe",
                "C:\\Users\\cuck\\AppData\\Local\\Temp\\files_list",
                "C:\\Users\\cuck\\AppData\\Local\\Temp\\browser_assistant.exe"
            ],
            "directory_created": [
                "C:\\Users\\cuck\\AppData\\Local\\Temp"
            ],
            "dll_loaded": [
                "kernel32",
                "kernel32.dll",
                "UxTheme.dll",
                "dwmapi.dll",
                "comctl32.dll",
                "C:\\Windows\\system32\\uxtheme.dll"
            ],
            "file_opened": [
                "C:\\Users\\cuck\\AppData\\Local\\Temp\\04ee0d96b396798f19bda2adfc22e90165b06f017e4123b61b5f68d52c70db01.bin",
                "C:\\Windows\\Globalization\\Sorting\\sortdefault.nls"
            ],
            "file_written": [
                "C:\\Users\\cuck\\AppData\\Local\\Temp\\assistant_installer.exe",
                "C:\\Users\\cuck\\AppData\\Local\\Temp\\files_list",
                "C:\\Users\\cuck\\AppData\\Local\\Temp\\browser_assistant.exe"
            ],
            "file_exists": [
                "C:\\Users\\cuck\\AppData\\Local\\Temp\\assistant_installer.exe",
                "C:\\Users\\cuck\\AppData\\Local\\Temp\\files_list",
                "C:\\Users\\cuck\\AppData\\Local\\Temp\\browser_assistant.exe",
                "C:\\Users\\cuck\\AppData\\Local\\Temp"
            ],
            "file_read": [
                "C:\\Users\\cuck\\AppData\\Local\\Temp\\04ee0d96b396798f19bda2adfc22e90165b06f017e4123b61b5f68d52c70db01.bin"
            ],
            "regkey_read": [
                "HKEY_LOCAL_MACHINE\\SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\GRE_Initialize\\DisableMetaFiles",
                "HKEY_LOCAL_MACHINE\\SYSTEM\\ControlSet001\\Control\\Nls\\CustomLocale\\en-US",
                "HKEY_LOCAL_MACHINE\\SYSTEM\\ControlSet001\\Control\\Nls\\ExtendedLocale\\en-US"
            ]
        },
        "first_seen": 1601459591.8125,
        "ppid": 2308
    },
    {
        "process_path": "C:\\Windows\\System32\\lsass.exe",
        "process_name": "lsass.exe",
        "pid": 476,
        "summary": {},
        "first_seen": 1601459591.546875,
        "ppid": 376
    }
]

Signatures

[
    {
        "markcount": 1,
        "families": [],
        "description": "Checks if process is being debugged by a debugger",
        "severity": 1,
        "marks": [
            {
                "call": {
                    "category": "system",
                    "status": 0,
                    "stacktrace": [],
                    "last_error": 0,
                    "nt_status": -1073741515,
                    "api": "IsDebuggerPresent",
                    "return_value": 0,
                    "arguments": {},
                    "time": 1601459591.8905,
                    "tid": 2436,
                    "flags": {}
                },
                "pid": 2740,
                "type": "call",
                "cid": 23
            }
        ],
        "references": [],
        "name": "checks_debugger"
    },
    {
        "markcount": 1,
        "families": [],
        "description": "Checks amount of memory in system, this can be used to detect virtual machines that have a low amount of memory available",
        "severity": 1,
        "marks": [
            {
                "call": {
                    "category": "system",
                    "status": 1,
                    "stacktrace": [],
                    "api": "GlobalMemoryStatusEx",
                    "return_value": 1,
                    "arguments": {},
                    "time": 1601459592.0785,
                    "tid": 2436,
                    "flags": {}
                },
                "pid": 2740,
                "type": "call",
                "cid": 1496
            }
        ],
        "references": [],
        "name": "antivm_memory_available"
    },
    {
        "markcount": 1,
        "families": [],
        "description": "The executable uses a known packer",
        "severity": 1,
        "marks": [
            {
                "category": "packer",
                "ioc": "Armadillo v1.71",
                "type": "ioc",
                "description": null
            }
        ],
        "references": [],
        "name": "peid_packer"
    },
    {
        "markcount": 1,
        "families": [],
        "description": "Queries the disk size which could be used to detect virtual machine with small fixed size or dynamic allocation",
        "severity": 2,
        "marks": [
            {
                "call": {
                    "category": "misc",
                    "status": 1,
                    "stacktrace": [],
                    "api": "GetDiskFreeSpaceExW",
                    "return_value": 1,
                    "arguments": {
                        "root_path": "C:\\Users\\cuck\\AppData\\Local\\Temp",
                        "free_bytes_available": 23514923008,
                        "total_number_of_free_bytes": 0,
                        "total_number_of_bytes": 0
                    },
                    "time": 1601459592.0785,
                    "tid": 2828,
                    "flags": {}
                },
                "pid": 2740,
                "type": "call",
                "cid": 1510
            }
        ],
        "references": [],
        "name": "antivm_disk_size"
    }
]

Yara

The Yara rules did not detect anything in the file.

Network

{
    "tls": [],
    "udp": [
        {
            "src": "192.168.56.101",
            "dst": "192.168.56.255",
            "offset": 662,
            "time": 6.221934080123901,
            "dport": 137,
            "sport": 137
        },
        {
            "src": "192.168.56.101",
            "dst": "224.0.0.252",
            "offset": 2134,
            "time": 6.156105995178223,
            "dport": 5355,
            "sport": 51001
        },
        {
            "src": "192.168.56.101",
            "dst": "224.0.0.252",
            "offset": 2462,
            "time": 4.1639580726623535,
            "dport": 5355,
            "sport": 53595
        },
        {
            "src": "192.168.56.101",
            "dst": "224.0.0.252",
            "offset": 2790,
            "time": 6.164698123931885,
            "dport": 5355,
            "sport": 53848
        },
        {
            "src": "192.168.56.101",
            "dst": "224.0.0.252",
            "offset": 3118,
            "time": 4.795671224594116,
            "dport": 5355,
            "sport": 54255
        },
        {
            "src": "192.168.56.101",
            "dst": "224.0.0.252",
            "offset": 3446,
            "time": 3.05953311920166,
            "dport": 5355,
            "sport": 55314
        },
        {
            "src": "192.168.56.101",
            "dst": "239.255.255.250",
            "offset": 3774,
            "time": 4.706629991531372,
            "dport": 1900,
            "sport": 1900
        },
        {
            "src": "192.168.56.101",
            "dst": "239.255.255.250",
            "offset": 7102,
            "time": 4.181635141372681,
            "dport": 3702,
            "sport": 49152
        },
        {
            "src": "192.168.56.101",
            "dst": "239.255.255.250",
            "offset": 11294,
            "time": 6.269325017929077,
            "dport": 1900,
            "sport": 53598
        }
    ],
    "dns_servers": [],
    "http": [],
    "icmp": [],
    "smtp": [],
    "tcp": [],
    "smtp_ex": [],
    "mitm": [],
    "hosts": [],
    "pcap_sha256": "6d06f6e608f163083d316556ba333bf4126e4a48072862c58e6f5721d0f606c0",
    "dns": [],
    "http_ex": [],
    "domains": [],
    "dead_hosts": [],
    "sorted_pcap_sha256": "e38d74700945119116c2270af4f993ecc6936987f30d5a982a7de455d2aa7ba8",
    "irc": [],
    "https_ex": []
}

Screenshots

Malware or legitimate?

If you feel that you need more information to determine if your should keep this file or remove it, please read this guide.

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