rule win_thunderx_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2024-10-31"
        version = "1"
        description = "Detects win.thunderx."
        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.thunderx"
        malpedia_rule_date = "20241030"
        malpedia_hash = "26e26953c49c8efafbf72a38076855d578e0a2e4"
        malpedia_version = "20241030"
        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 = { 8b4598 03c1 894d8c 6a0d 50 e8???????? 33f8 }
            // n = 7, score = 200
            //   8b4598               | mov                 eax, dword ptr [ebp - 0x68]
            //   03c1                 | add                 eax, ecx
            //   894d8c               | mov                 dword ptr [ebp - 0x74], ecx
            //   6a0d                 | push                0xd
            //   50                   | push                eax
            //   e8????????           |                     
            //   33f8                 | xor                 edi, eax

        $sequence_1 = { 57 b9???????? e8???????? 83f8ff 7413 837e1410 7202 }
            // n = 7, score = 200
            //   57                   | push                edi
            //   b9????????           |                     
            //   e8????????           |                     
            //   83f8ff               | cmp                 eax, -1
            //   7413                 | je                  0x15
            //   837e1410             | cmp                 dword ptr [esi + 0x14], 0x10
            //   7202                 | jb                  4

        $sequence_2 = { e8???????? 83c618 3b742428 75f0 8d4c2424 e8???????? e8???????? }
            // n = 7, score = 200
            //   e8????????           |                     
            //   83c618               | add                 esi, 0x18
            //   3b742428             | cmp                 esi, dword ptr [esp + 0x28]
            //   75f0                 | jne                 0xfffffff2
            //   8d4c2424             | lea                 ecx, [esp + 0x24]
            //   e8????????           |                     
            //   e8????????           |                     

        $sequence_3 = { e8???????? 83c618 8975c0 eb0d 57 56 }
            // n = 6, score = 200
            //   e8????????           |                     
            //   83c618               | add                 esi, 0x18
            //   8975c0               | mov                 dword ptr [ebp - 0x40], esi
            //   eb0d                 | jmp                 0xf
            //   57                   | push                edi
            //   56                   | push                esi

        $sequence_4 = { 8b36 53 56 ff7710 50 e8???????? 5e }
            // n = 7, score = 200
            //   8b36                 | mov                 esi, dword ptr [esi]
            //   53                   | push                ebx
            //   56                   | push                esi
            //   ff7710               | push                dword ptr [edi + 0x10]
            //   50                   | push                eax
            //   e8????????           |                     
            //   5e                   | pop                 esi

        $sequence_5 = { 50 ff15???????? 85c0 0f85b7000000 837e1408 7202 8b36 }
            // n = 7, score = 200
            //   50                   | push                eax
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax
            //   0f85b7000000         | jne                 0xbd
            //   837e1408             | cmp                 dword ptr [esi + 0x14], 8
            //   7202                 | jb                  4
            //   8b36                 | mov                 esi, dword ptr [esi]

        $sequence_6 = { 56 57 6a66 50 ff15???????? 51 50 }
            // n = 7, score = 200
            //   56                   | push                esi
            //   57                   | push                edi
            //   6a66                 | push                0x66
            //   50                   | push                eax
            //   ff15????????         |                     
            //   51                   | push                ecx
            //   50                   | push                eax

        $sequence_7 = { e8???????? eb24 8d4de0 e8???????? }
            // n = 4, score = 200
            //   e8????????           |                     
            //   eb24                 | jmp                 0x26
            //   8d4de0               | lea                 ecx, [ebp - 0x20]
            //   e8????????           |                     

        $sequence_8 = { 8932 897204 897208 5e 5d c20400 6a18 }
            // n = 7, score = 200
            //   8932                 | mov                 dword ptr [edx], esi
            //   897204               | mov                 dword ptr [edx + 4], esi
            //   897208               | mov                 dword ptr [edx + 8], esi
            //   5e                   | pop                 esi
            //   5d                   | pop                 ebp
            //   c20400               | ret                 4
            //   6a18                 | push                0x18

        $sequence_9 = { 57 8955fc 8b7a14 8bc7 8b7210 2bc6 }
            // n = 6, score = 200
            //   57                   | push                edi
            //   8955fc               | mov                 dword ptr [ebp - 4], edx
            //   8b7a14               | mov                 edi, dword ptr [edx + 0x14]
            //   8bc7                 | mov                 eax, edi
            //   8b7210               | mov                 esi, dword ptr [edx + 0x10]
            //   2bc6                 | sub                 eax, esi

    condition:
        7 of them and filesize < 319488
}

import "pe"

rule win_thunderx_w0 {
   meta:
      description = "Rule to dettect tthe ThunderX ransomware family"
      author = "Christiaan Beek @ McAfee ATR team"
      date = "2020-09-14"
      rule_version = "v1"
      malware_type = "ransomware"
      malware_family = "Ransomware:W32/ThunderX"
      actor_type = "Cybercrime"
      actor_group = "Unknown"
      hash1 = "7bab5dedef124803668580a59b6bf3c53cc31150d19591567397bbc131b9ccb6"
      hash2 = "0fbfdb8340108fafaca4c5ff4d3c9f9a2296efeb9ae89fcd9210e3d4c7239666"
      hash3 = "7527459500109b3bb48665236c5c5cb2ec71ba789867ad2b6417b38b9a46615e"
      source = "https://github.com/advanced-threat-research/Yara-Rules/blob/master/ransomware/Ransom_ThunderX.yar"
      malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.thunderx"
      malpedia_rule_date = "20200915"
      malpedia_hash = ""
      malpedia_version = "20200915"
      malpedia_license = "CC BY-SA 4.0"
      malpedia_sharing = "TLP:WHITE"

   strings:
   
      $pattern1 = "626364656469742E657865202F736574207B64656661756C747D20626F6F74737461747573706F6C6963792069676E6F7265616C6C6661696C75726573" 
     
      $s3 = "776261646D696E2044454C4554452053595354454D53544154454241434B5550202D64656C6574654F6C64657374" ascii
      $s4 = "626364656469742E657865202F736574207B64656661756C747D207265636F76657279656E61626C6564204E6F" ascii 
      $s5 = "776261646D696E2044454C4554452053595354454D53544154454241434B5550" ascii 
      $s6 = "433A5C50726F6772616D2046696C65732028783836295C4D6963726F736F66742053514C20536572766572" ascii 
      $s7 = "476C6F62616C5C33353335354641352D303745392D343238422D423541352D314338384341423242343838" ascii 
      $s8 = "433A5C50726F6772616D2046696C65735C4D6963726F736F66742053514C20536572766572" ascii 
      $s9 = "76737361646D696E2E6578652044656C65746520536861646F7773202F416C6C202F5175696574" ascii 
      $s10 = "776D69632E65786520534841444F57434F5059202F6E6F696E746572616374697665" ascii 
      $s11 = "534F4654574152455C4D6963726F736F66745C45524944" ascii 
      $s12 = "AppPolicyGetProcessTerminationMethod" fullword ascii
      $s13 = "7B5041545445524E5F49447D" ascii 
      $s14 = "726561646D652E747874" ascii 
      $s15 = "226E6574776F726B223A22" ascii 
      $s16 = "227375626964223A22" ascii 
      $s17 = "226C616E67223A22" ascii 
      $s18 = "22657874223A22" ascii 
      $s19 = "69642E6B6579" ascii 
      $s20 = "7B5549447D" ascii 

      $seq0 = { eb 34 66 0f 12 0d 10 c4 41 00 f2 0f 59 c1 ba cc }
      $seq1 = { 6a 07 50 e8 51 ff ff ff 8d 86 d0 }
      $seq2 = { ff 15 34 81 41 00 eb 15 83 f8 fc 75 10 8b 45 f4 }
   condition:
      ( uint16(0) == 0x5a4d and filesize < 400KB and pe.imphash() == "ea7e408cd2a264fd13492973e97d8d70" and $pattern1 and 4 of them ) and all of ($seq*) or ( all of them )
}