rule win_plugx_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2020-05-30"
        version = "1"
        description = "autogenerated rule brought to you by yara-signator"
        tool = "yara-signator v0.4.0"
        tool_config = "callsandjumps;datarefs;binvalue"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.plugx"
        malpedia_rule_date = "20200529"
        malpedia_hash = "92c362319514e5a6da26204961446caa3a8b32a8"
        malpedia_version = "20200529"
        malpedia_license = "CC BY-NC-SA 4.0"
        malpedia_sharing = "TLP:WHITE"

    /* DISCLAIMER
     * The strings used in this rule have been automatically selected from the
     * disassembly of memory dumps and unpacked files, using yara-signator.
     * The code and documentation / approach is published here:
     * https://github.com/fxb-cocacoding/yara-signator
     * As Malpedia is used as data source, please note that for a given
     * number of families, only single samples are documented.
     * This likely impacts the degree of generalization these rules will offer.
     * Take the described generation method also into consideration when you
     * apply the rules in your use cases and assign them confidence levels.
     */


    strings:
        $sequence_0 = { 59 8bc8 e8???????? 8bc6 }
            // n = 4, score = 1000
            //   59                   | pop                 ecx
            //   8bc8                 | mov                 ecx, eax
            //   e8????????           |                     
            //   8bc6                 | mov                 eax, esi

        $sequence_1 = { 2b462c 2b4f10 8945fc 3bc1 7c03 894dfc 8b4610 }
            // n = 7, score = 1000
            //   2b462c               | sub                 eax, dword ptr [esi + 0x2c]
            //   2b4f10               | sub                 ecx, dword ptr [edi + 0x10]
            //   8945fc               | mov                 dword ptr [ebp - 4], eax
            //   3bc1                 | cmp                 eax, ecx
            //   7c03                 | jl                  5
            //   894dfc               | mov                 dword ptr [ebp - 4], ecx
            //   8b4610               | mov                 eax, dword ptr [esi + 0x10]

        $sequence_2 = { b8e5030000 eb03 6a57 58 }
            // n = 4, score = 1000
            //   b8e5030000           | mov                 eax, 0x3e5
            //   eb03                 | jmp                 5
            //   6a57                 | push                0x57
            //   58                   | pop                 eax

        $sequence_3 = { 8bec 51 56 57 6a1c 8bf8 e8???????? }
            // n = 7, score = 1000
            //   8bec                 | mov                 ebp, esp
            //   51                   | push                ecx
            //   56                   | push                esi
            //   57                   | push                edi
            //   6a1c                 | push                0x1c
            //   8bf8                 | mov                 edi, eax
            //   e8????????           |                     

        $sequence_4 = { 6a01 ff7508 56 e8???????? 59 }
            // n = 5, score = 1000
            //   6a01                 | push                1
            //   ff7508               | push                dword ptr [ebp + 8]
            //   56                   | push                esi
            //   e8????????           |                     
            //   59                   | pop                 ecx

        $sequence_5 = { ff750c e8???????? 8bf8 56 6a01 }
            // n = 5, score = 1000
            //   ff750c               | push                dword ptr [ebp + 0xc]
            //   e8????????           |                     
            //   8bf8                 | mov                 edi, eax
            //   56                   | push                esi
            //   6a01                 | push                1

        $sequence_6 = { 895c2430 895c242c 895c2424 e8???????? }
            // n = 4, score = 1000
            //   895c2430             | mov                 dword ptr [esp + 0x30], ebx
            //   895c242c             | mov                 dword ptr [esp + 0x2c], ebx
            //   895c2424             | mov                 dword ptr [esp + 0x24], ebx
            //   e8????????           |                     

        $sequence_7 = { 894dec e8???????? 59 57 ff75f0 53 56 }
            // n = 7, score = 1000
            //   894dec               | mov                 dword ptr [ebp - 0x14], ecx
            //   e8????????           |                     
            //   59                   | pop                 ecx
            //   57                   | push                edi
            //   ff75f0               | push                dword ptr [ebp - 0x10]
            //   53                   | push                ebx
            //   56                   | push                esi

        $sequence_8 = { 75f6 b8e5030000 eb03 6a57 58 5f 5e }
            // n = 7, score = 1000
            //   75f6                 | jne                 0xfffffff8
            //   b8e5030000           | mov                 eax, 0x3e5
            //   eb03                 | jmp                 5
            //   6a57                 | push                0x57
            //   58                   | pop                 eax
            //   5f                   | pop                 edi
            //   5e                   | pop                 esi

        $sequence_9 = { e8???????? 8b45fc 01470c 014710 01462c 8b462c 83c40c }
            // n = 7, score = 1000
            //   e8????????           |                     
            //   8b45fc               | mov                 eax, dword ptr [ebp - 4]
            //   01470c               | add                 dword ptr [edi + 0xc], eax
            //   014710               | add                 dword ptr [edi + 0x10], eax
            //   01462c               | add                 dword ptr [esi + 0x2c], eax
            //   8b462c               | mov                 eax, dword ptr [esi + 0x2c]
            //   83c40c               | add                 esp, 0xc

    condition:
        7 of them and filesize < 598016
}

rule win_plugx_w1 {
    meta:
        description = "PlugX Identifying Strings"
        author = "Seth Hardy"
        last_modified = "2014-06-12"
		source = "https://github.com/mattulm/sfiles_yara/blob/master/malware/plugx.yar"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.plugx"
        malpedia_version = "20170517"
        malpedia_license = "CC BY-NC-SA 4.0"
        malpedia_sharing = "TLP:WHITE"
        
    strings:
        $BootLDR = "boot.ldr" wide ascii
        $Dwork = "d:\\work" nocase
        $Plug25 = "plug2.5"
        $Plug30 = "Plug3.0"
        $Shell6 = "Shell6"
      
    condition:
        $BootLDR or ($Dwork and ($Plug25 or $Plug30 or $Shell6))
}

rule win_plugx_w2 {
	meta:
		author = "Jean-Philippe Teissier / @Jipe_"
		description = "PlugX RAT"
		date = "2014-05-13"
		filetype = "memory"
		version = "1.0" 
		ref1 = "https://github.com/mattulm/IR-things/blob/master/volplugs/plugx.py"
		source = "https://github.com/mattulm/sfiles_yara/blob/master/malware/plugx.yar"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.plugx"
        malpedia_version = "20170517"
        malpedia_license = "CC BY-NC-SA 4.0"
        malpedia_sharing = "TLP:WHITE"
		
	strings:
		$v1a = { 47 55 4C 50 00 00 00 00 }
		$v1b = "/update?id=%8.8x" 
		$v1algoa = { BB 33 33 33 33 2B } 
		$v1algob = { BB 44 44 44 44 2B } 
		$v2a = "Proxy-Auth:" 
		$v2b = { 68 A0 02 00 00 } 
		$v2k = { C1 8F 3A 71 } 
		
	condition: 
		$v1a at 0 or $v1b or (($v2a or $v2b) and (($v1algoa and $v1algob) or $v2k))
}