APT_Minidionis.yar

/*
    This Yara ruleset is under the GNU-GPLv2 license (http://www.gnu.org/licenses/gpl-2.0.html) and open to any user or organization, as    long as you use it under this license.

*/

rule MiniDionis_readerView 
{

    meta:
        description = "MiniDionis Malware - file readerView.exe / adobe.exe"
        author = "Florian Roth"
        reference = "http://www.kernelmode.info/forum/viewtopic.php?f=16&t=3950"
        date = "2015-07-20"
        /* Original Hash */
        hash1 = "ee5eb9d57c3611e91a27bb1fc2d0aaa6bbfa6c69ab16e65e7123c7c49d46f145"
        /* Derived Samples */
        hash2 = "a713982d04d2048a575912a5fc37c93091619becd5b21e96f049890435940004"
        hash3 = "88a40d5b679bccf9641009514b3d18b09e68b609ffaf414574a6eca6536e8b8f"
        hash4 = "97d8725e39d263ed21856477ed09738755134b5c0d0b9ae86ebb1cdd4cdc18b7"
        hash5 = "ed7abf93963395ce9c9cba83a864acb4ed5b6e57fd9a6153f0248b8ccc4fdb46"
        hash6 = "56ac764b81eb216ebed5a5ad38e703805ba3e1ca7d63501ba60a1fb52c7ebb6e"

    strings:
        $s1 = "%ws_out%ws" fullword wide /* score: '8.00' */
        $s2 = "dnlibsh" fullword ascii /* score: '7.00' */

        $op0 = { 0f b6 80 68 0e 41 00 0b c8 c1 e1 08 0f b6 c2 8b } /* Opcode */
        $op1 = { 8b ce e8 f8 01 00 00 85 c0 74 41 83 7d f8 00 0f } /* Opcode */
        $op2 = { e8 2f a2 ff ff 83 20 00 83 c8 ff 5f 5e 5d c3 55 } /* Opcode */

    condition:
        uint16(0) == 0x5a4d and filesize < 500KB and all of ($s*) and 1 of ($op*)
}

/* Related - SFX files or packed files with typical malware content -------- */

rule Malicious_SFX1 
{

    meta:
        description = "SFX with voicemail content"
        author = "Florian Roth"
        reference = "http://www.kernelmode.info/forum/viewtopic.php?f=16&t=3950"
        date = "2015-07-20"
        hash = "c0675b84f5960e95962d299d4c41511bbf6f8f5f5585bdacd1ae567e904cb92f"
   
    strings:
        $s0 = "voicemail" ascii /* PEStudio Blacklist: strings */ /* score: '30.00' */
        $s1 = ".exe" ascii
   
    condition:
        uint16(0) == 0x4b50 and filesize < 1000KB and $s0 in (3..80) and $s1 in (3..80) 
}

rule Malicious_SFX2 
{

    meta:
        description = "SFX with adobe.exe content"
        author = "Florian Roth"
        reference = "http://www.kernelmode.info/forum/viewtopic.php?f=16&t=3950"
        date = "2015-07-20"
        hash = "502e42dc99873c52c3ca11dd3df25aad40d2b083069e8c22dd45da887f81d14d"

    strings:
        $s1 = "adobe.exe" fullword ascii /* PEStudio Blacklist: strings */ /* score: '27.00' */
        $s2 = "Extracting files to %s folder$Extracting files to temporary folder" fullword wide /* PEStudio Blacklist: strings */ /* score: '26.00' */
        $s3 = "GETPASSWORD1" fullword wide /* PEStudio Blacklist: strings */ /* score: '23.00' */

    condition:
        uint16(0) == 0x5a4d and filesize < 1000KB and all of them
}

rule MiniDionis_VBS_Dropped 
{

    meta:
        description = "Dropped File - 1.vbs"
        author = "Florian Roth"
        reference = "https://malwr.com/analysis/ZDc4ZmIyZDI4MTVjNGY5NWI0YzE3YjIzNGFjZTcyYTY/"
        date = "2015-07-21"
        hash = "97dd1ee3aca815eb655a5de9e9e8945e7ba57f458019be6e1b9acb5731fa6646"

    strings:
        $s1 = "Wscript.Sleep 5000" ascii
        $s2 = "Set FSO = CreateObject(\"Scripting.FileSystemObject\")" ascii
        $s3 = "Set WshShell = CreateObject(\"WScript.Shell\")" ascii
        $s4 = "If(FSO.FileExists(\"" ascii
        $s5 = "then FSO.DeleteFile(\".\\" ascii

    condition:
        filesize < 1KB and all of them and $s1 in (0..40)
}