rule win_derusbi_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2023-07-11"
        version = "1"
        description = "Detects win.derusbi."
        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.derusbi"
        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 = { 8d04c51f000000 83e0e0 99 83e207 8d1c02 c1fb03 0faf5da0 }
            // n = 7, score = 200
            //   8d04c51f000000       | lea                 eax, [eax*8 + 0x1f]
            //   83e0e0               | and                 eax, 0xffffffe0
            //   99                   | cdq                 
            //   83e207               | and                 edx, 7
            //   8d1c02               | lea                 ebx, [edx + eax]
            //   c1fb03               | sar                 ebx, 3
            //   0faf5da0             | imul                ebx, dword ptr [ebp - 0x60]

        $sequence_1 = { 68???????? ffb5f4fbffff c785f8fbffffff030000 ff15???????? 85c0 754f 83bdf0fbffff03 }
            // n = 7, score = 200
            //   68????????           |                     
            //   ffb5f4fbffff         | push                dword ptr [ebp - 0x40c]
            //   c785f8fbffffff030000     | mov    dword ptr [ebp - 0x408], 0x3ff
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax
            //   754f                 | jne                 0x51
            //   83bdf0fbffff03       | cmp                 dword ptr [ebp - 0x410], 3

        $sequence_2 = { 8d85bcfcffff 50 68???????? eb40 68???????? 56 ff15???????? }
            // n = 7, score = 200
            //   8d85bcfcffff         | lea                 eax, [ebp - 0x344]
            //   50                   | push                eax
            //   68????????           |                     
            //   eb40                 | jmp                 0x42
            //   68????????           |                     
            //   56                   | push                esi
            //   ff15????????         |                     

        $sequence_3 = { 7519 8d85fcfeffff 68???????? 50 ffd6 83bde4fdffff06 59 }
            // n = 7, score = 200
            //   7519                 | jne                 0x1b
            //   8d85fcfeffff         | lea                 eax, [ebp - 0x104]
            //   68????????           |                     
            //   50                   | push                eax
            //   ffd6                 | call                esi
            //   83bde4fdffff06       | cmp                 dword ptr [ebp - 0x21c], 6
            //   59                   | pop                 ecx

        $sequence_4 = { 8b86b4200000 89742410 85c0 7415 6a00 ff7310 8d4b14 }
            // n = 7, score = 200
            //   8b86b4200000         | mov                 eax, dword ptr [esi + 0x20b4]
            //   89742410             | mov                 dword ptr [esp + 0x10], esi
            //   85c0                 | test                eax, eax
            //   7415                 | je                  0x17
            //   6a00                 | push                0
            //   ff7310               | push                dword ptr [ebx + 0x10]
            //   8d4b14               | lea                 ecx, [ebx + 0x14]

        $sequence_5 = { 6a01 ffd7 33c0 40 8b4dfc 5f 5e }
            // n = 7, score = 200
            //   6a01                 | push                1
            //   ffd7                 | call                edi
            //   33c0                 | xor                 eax, eax
            //   40                   | inc                 eax
            //   8b4dfc               | mov                 ecx, dword ptr [ebp - 4]
            //   5f                   | pop                 edi
            //   5e                   | pop                 esi

        $sequence_6 = { e8???????? c9 c3 55 8bec 81ec4c020000 }
            // n = 6, score = 200
            //   e8????????           |                     
            //   c9                   | leave               
            //   c3                   | ret                 
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp
            //   81ec4c020000         | sub                 esp, 0x24c

        $sequence_7 = { ffb5f4fdffff ff15???????? 59 8bd8 8d85f4fdffff 50 53 }
            // n = 7, score = 200
            //   ffb5f4fdffff         | push                dword ptr [ebp - 0x20c]
            //   ff15????????         |                     
            //   59                   | pop                 ecx
            //   8bd8                 | mov                 ebx, eax
            //   8d85f4fdffff         | lea                 eax, [ebp - 0x20c]
            //   50                   | push                eax
            //   53                   | push                ebx

        $sequence_8 = { 50 8d8320020000 50 ff15???????? 83c40c 8d8338040000 50 }
            // n = 7, score = 200
            //   50                   | push                eax
            //   8d8320020000         | lea                 eax, [ebx + 0x220]
            //   50                   | push                eax
            //   ff15????????         |                     
            //   83c40c               | add                 esp, 0xc
            //   8d8338040000         | lea                 eax, [ebx + 0x438]
            //   50                   | push                eax

        $sequence_9 = { 5b 8b8c24200a0000 33cc e8???????? 8be5 5d c20800 }
            // n = 7, score = 200
            //   5b                   | pop                 ebx
            //   8b8c24200a0000       | mov                 ecx, dword ptr [esp + 0xa20]
            //   33cc                 | xor                 ecx, esp
            //   e8????????           |                     
            //   8be5                 | mov                 esp, ebp
            //   5d                   | pop                 ebp
            //   c20800               | ret                 8

    condition:
        7 of them and filesize < 360448
}