rule win_plugx_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2023-07-11"
        version = "1"
        description = "Detects win.plugx."
        info = "autogenerated rule brought to you by yara-signator"
        tool = "yara-signator v0.6.0"
        signator_config = "callsandjumps;datarefs;binvalue"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.plugx"
        malpedia_rule_date = "20230705"
        malpedia_hash = "42d0574f4405bd7d2b154d321d345acb18834a41"
        malpedia_version = "20230715"
        malpedia_license = "CC BY-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 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 = { 56 8b750c 8b4604 050070ffff }
            // n = 4, score = 1300
            //   56                   | push                esi
            //   8b750c               | mov                 esi, dword ptr [ebp + 0xc]
            //   8b4604               | mov                 eax, dword ptr [esi + 4]
            //   050070ffff           | add                 eax, 0xffff7000

        $sequence_1 = { 55 8bec 8b450c 81780402700000 }
            // n = 4, score = 1300
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp
            //   8b450c               | mov                 eax, dword ptr [ebp + 0xc]
            //   81780402700000       | cmp                 dword ptr [eax + 4], 0x7002

        $sequence_2 = { 0145f4 8b45fc 0fafc3 33d2 }
            // n = 4, score = 1300
            //   0145f4               | add                 dword ptr [ebp - 0xc], eax
            //   8b45fc               | mov                 eax, dword ptr [ebp - 4]
            //   0fafc3               | imul                eax, ebx
            //   33d2                 | xor                 edx, edx

        $sequence_3 = { 55 8bec a1???????? 83ec5c 53 }
            // n = 5, score = 1300
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp
            //   a1????????           |                     
            //   83ec5c               | sub                 esp, 0x5c
            //   53                   | push                ebx

        $sequence_4 = { 41 3bca 7ce0 3bca }
            // n = 4, score = 1300
            //   41                   | inc                 ecx
            //   3bca                 | cmp                 ecx, edx
            //   7ce0                 | jl                  0xffffffe2
            //   3bca                 | cmp                 ecx, edx

        $sequence_5 = { 55 8bec 51 0fb74612 }
            // n = 4, score = 1300
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp
            //   51                   | push                ecx
            //   0fb74612             | movzx               eax, word ptr [esi + 0x12]

        $sequence_6 = { 51 53 6a00 6a00 6a02 ffd0 }
            // n = 6, score = 1300
            //   51                   | push                ecx
            //   53                   | push                ebx
            //   6a00                 | push                0
            //   6a00                 | push                0
            //   6a02                 | push                2
            //   ffd0                 | call                eax

        $sequence_7 = { 51 56 57 6a1c 8bf8 e8???????? 8bf0 }
            // n = 7, score = 1300
            //   51                   | push                ecx
            //   56                   | push                esi
            //   57                   | push                edi
            //   6a1c                 | push                0x1c
            //   8bf8                 | mov                 edi, eax
            //   e8????????           |                     
            //   8bf0                 | mov                 esi, eax

        $sequence_8 = { 6a00 6a04 6a00 6a01 6800000040 57 }
            // n = 6, score = 700
            //   6a00                 | push                0
            //   6a04                 | push                4
            //   6a00                 | push                0
            //   6a01                 | push                1
            //   6800000040           | push                0x40000000
            //   57                   | push                edi

        $sequence_9 = { 56 56 6a01 56 ffd0 }
            // n = 5, score = 600
            //   56                   | push                esi
            //   56                   | push                esi
            //   6a01                 | push                1
            //   56                   | push                esi
            //   ffd0                 | call                eax

        $sequence_10 = { 6a00 6819000200 6a00 6a00 6a00 51 }
            // n = 6, score = 600
            //   6a00                 | push                0
            //   6819000200           | push                0x20019
            //   6a00                 | push                0
            //   6a00                 | push                0
            //   6a00                 | push                0
            //   51                   | push                ecx

        $sequence_11 = { 50 ff75e8 6802000080 e8???????? }
            // n = 4, score = 400
            //   50                   | push                eax
            //   ff75e8               | push                dword ptr [ebp - 0x18]
            //   6802000080           | push                0x80000002
            //   e8????????           |                     

        $sequence_12 = { 50 56 ffb42480000000 ff15???????? }
            // n = 4, score = 400
            //   50                   | push                eax
            //   56                   | push                esi
            //   ffb42480000000       | push                dword ptr [esp + 0x80]
            //   ff15????????         |                     

        $sequence_13 = { 55 53 57 56 83ec2c a1???????? }
            // n = 6, score = 400
            //   55                   | push                ebp
            //   53                   | push                ebx
            //   57                   | push                edi
            //   56                   | push                esi
            //   83ec2c               | sub                 esp, 0x2c
            //   a1????????           |                     

        $sequence_14 = { 6a00 ff7028 e8???????? 83c408 85c0 }
            // n = 5, score = 400
            //   6a00                 | push                0
            //   ff7028               | push                dword ptr [eax + 0x28]
            //   e8????????           |                     
            //   83c408               | add                 esp, 8
            //   85c0                 | test                eax, eax

        $sequence_15 = { 6808020000 6a00 ff74242c e8???????? }
            // n = 4, score = 400
            //   6808020000           | push                0x208
            //   6a00                 | push                0
            //   ff74242c             | push                dword ptr [esp + 0x2c]
            //   e8????????           |                     

        $sequence_16 = { 6808020000 6a00 ff742450 e8???????? 83c40c }
            // n = 5, score = 400
            //   6808020000           | push                0x208
            //   6a00                 | push                0
            //   ff742450             | push                dword ptr [esp + 0x50]
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc

        $sequence_17 = { 5f 5b 5d c20400 55 53 }
            // n = 6, score = 400
            //   5f                   | pop                 edi
            //   5b                   | pop                 ebx
            //   5d                   | pop                 ebp
            //   c20400               | ret                 4
            //   55                   | push                ebp
            //   53                   | push                ebx

        $sequence_18 = { 5b 5d c3 64a118000000 }
            // n = 4, score = 400
            //   5b                   | pop                 ebx
            //   5d                   | pop                 ebp
            //   c3                   | ret                 
            //   64a118000000         | mov                 eax, dword ptr fs:[0x18]

        $sequence_19 = { 83c40c c78550ffffff28000000 8b4df0 898d6cffffff c78568ffffff00000000 6a00 6a00 }
            // n = 7, score = 100
            //   83c40c               | add                 esp, 0xc
            //   c78550ffffff28000000     | mov    dword ptr [ebp - 0xb0], 0x28
            //   8b4df0               | mov                 ecx, dword ptr [ebp - 0x10]
            //   898d6cffffff         | mov                 dword ptr [ebp - 0x94], ecx
            //   c78568ffffff00000000     | mov    dword ptr [ebp - 0x98], 0
            //   6a00                 | push                0
            //   6a00                 | push                0

        $sequence_20 = { e8???????? 8945f8 837df800 7405 e9???????? 8d4ddc e8???????? }
            // n = 7, score = 100
            //   e8????????           |                     
            //   8945f8               | mov                 dword ptr [ebp - 8], eax
            //   837df800             | cmp                 dword ptr [ebp - 8], 0
            //   7405                 | je                  7
            //   e9????????           |                     
            //   8d4ddc               | lea                 ecx, [ebp - 0x24]
            //   e8????????           |                     

        $sequence_21 = { 8b55f0 83c208 8955ec 8b45e8 8945a0 }
            // n = 5, score = 100
            //   8b55f0               | mov                 edx, dword ptr [ebp - 0x10]
            //   83c208               | add                 edx, 8
            //   8955ec               | mov                 dword ptr [ebp - 0x14], edx
            //   8b45e8               | mov                 eax, dword ptr [ebp - 0x18]
            //   8945a0               | mov                 dword ptr [ebp - 0x60], eax

        $sequence_22 = { 8d4df4 e8???????? 8b5508 52 8d4df4 e8???????? 68???????? }
            // n = 7, score = 100
            //   8d4df4               | lea                 ecx, [ebp - 0xc]
            //   e8????????           |                     
            //   8b5508               | mov                 edx, dword ptr [ebp + 8]
            //   52                   | push                edx
            //   8d4df4               | lea                 ecx, [ebp - 0xc]
            //   e8????????           |                     
            //   68????????           |                     

        $sequence_23 = { b832000000 668945ba b92e000000 66894dbc ba32000000 }
            // n = 5, score = 100
            //   b832000000           | mov                 eax, 0x32
            //   668945ba             | mov                 word ptr [ebp - 0x46], ax
            //   b92e000000           | mov                 ecx, 0x2e
            //   66894dbc             | mov                 word ptr [ebp - 0x44], cx
            //   ba32000000           | mov                 edx, 0x32

        $sequence_24 = { 55 8bec 81ec78060000 33c0 66898590fbffff }
            // n = 5, score = 100
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp
            //   81ec78060000         | sub                 esp, 0x678
            //   33c0                 | xor                 eax, eax
            //   66898590fbffff       | mov                 word ptr [ebp - 0x470], ax

        $sequence_25 = { 50 e8???????? 83c40c 33c9 66898dbcfbffff 6806020000 }
            // n = 6, score = 100
            //   50                   | push                eax
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc
            //   33c9                 | xor                 ecx, ecx
            //   66898dbcfbffff       | mov                 word ptr [ebp - 0x444], cx
            //   6806020000           | push                0x206

        $sequence_26 = { 668995a8eaffff 6806020000 6a00 8d85aaeaffff 50 e8???????? }
            // n = 6, score = 100
            //   668995a8eaffff       | mov                 word ptr [ebp - 0x1558], dx
            //   6806020000           | push                0x206
            //   6a00                 | push                0
            //   8d85aaeaffff         | lea                 eax, [ebp - 0x1556]
            //   50                   | push                eax
            //   e8????????           |                     

    condition:
        7 of them and filesize < 1284096
}

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))
}