rule win_crosswalk_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2023-01-25"
        version = "1"
        description = "Detects win.crosswalk."
        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.crosswalk"
        malpedia_rule_date = "20230124"
        malpedia_hash = "2ee0eebba83dce3d019a90519f2f972c0fcf9686"
        malpedia_version = "20230125"
        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 = { 33f6 8d6e20 8bcd e8???????? }
            // n = 4, score = 1300
            //   33f6                 | mov                 eax, esi
            //   8d6e20               | xor                 edx, edx
            //   8bcd                 | inc                 ecx
            //   e8????????           |                     

        $sequence_1 = { 410fbe00 49ffc0 d3ca 03d0 4183ef01 }
            // n = 5, score = 1300
            //   410fbe00             | inc                 ecx
            //   49ffc0               | movsx               eax, byte ptr [eax]
            //   d3ca                 | dec                 ecx
            //   03d0                 | inc                 eax
            //   4183ef01             | ror                 edx, cl

        $sequence_2 = { 458bc6 33d2 488bc8 e8???????? 4533c9 4533c0 }
            // n = 6, score = 1300
            //   458bc6               | mov                 eax, eax
            //   33d2                 | imul                ecx
            //   488bc8               | add                 edx, ecx
            //   e8????????           |                     
            //   4533c9               | sar                 edx, 0xb
            //   4533c0               | mov                 eax, edx

        $sequence_3 = { ff15???????? 448bf0 4533c9 4533c0 }
            // n = 4, score = 1300
            //   ff15????????         |                     
            //   448bf0               | inc                 ecx
            //   4533c9               | movsx               eax, byte ptr [eax]
            //   4533c0               | dec                 ecx

        $sequence_4 = { 4c8bc6 33d2 410fbe00 49ffc0 }
            // n = 4, score = 1300
            //   4c8bc6               | inc                 ebp
            //   33d2                 | mov                 eax, esi
            //   410fbe00             | xor                 edx, edx
            //   49ffc0               | dec                 eax

        $sequence_5 = { c1fa0b 8bc2 c1e81f 03d0 69c2890e0000 }
            // n = 5, score = 1300
            //   c1fa0b               | add                 edx, eax
            //   8bc2                 | inc                 ecx
            //   c1e81f               | sub                 edi, 1
            //   03d0                 | inc                 ebp
            //   69c2890e0000         | mov                 eax, esi

        $sequence_6 = { 41b88d56e68c 418bc0 f7e9 03d1 c1fa0b 8bc2 }
            // n = 6, score = 1300
            //   41b88d56e68c         | add                 edx, eax
            //   418bc0               | inc                 ecx
            //   f7e9                 | sub                 edi, 1
            //   03d1                 | inc                 ecx
            //   c1fa0b               | mov                 eax, 0x8ce6568d
            //   8bc2                 | inc                 ecx

        $sequence_7 = { 458d7ee0 418bd7 ff15???????? 4821742420 }
            // n = 4, score = 1300
            //   458d7ee0             | inc                 ecx
            //   418bd7               | sub                 edi, 1
            //   ff15????????         |                     
            //   4821742420           | dec                 esp

        $sequence_8 = { eb17 81fa00010000 7313 8a87f4814100 08441619 }
            // n = 5, score = 200
            //   eb17                 | jmp                 0x19
            //   81fa00010000         | cmp                 edx, 0x100
            //   7313                 | jae                 0x15
            //   8a87f4814100         | mov                 al, byte ptr [edi + 0x4181f4]
            //   08441619             | or                  byte ptr [esi + edx + 0x19], al

        $sequence_9 = { eb7c c745e0205b4100 ebbb d9e8 8b4510 }
            // n = 5, score = 200
            //   eb7c                 | jmp                 0x7e
            //   c745e0205b4100       | mov                 dword ptr [ebp - 0x20], 0x415b20
            //   ebbb                 | jmp                 0xffffffbd
            //   d9e8                 | fld1                
            //   8b4510               | mov                 eax, dword ptr [ebp + 0x10]

        $sequence_10 = { c1e002 50 8b85b4f8ffff 0fb70485c4574100 8d0485c04e4100 50 }
            // n = 6, score = 200
            //   c1e002               | shl                 eax, 2
            //   50                   | push                eax
            //   8b85b4f8ffff         | mov                 eax, dword ptr [ebp - 0x74c]
            //   0fb70485c4574100     | movzx               eax, word ptr [eax*4 + 0x4157c4]
            //   8d0485c04e4100       | lea                 eax, [eax*4 + 0x414ec0]
            //   50                   | push                eax

        $sequence_11 = { ff15???????? 85c0 7f32 68???????? }
            // n = 4, score = 200
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax
            //   7f32                 | jg                  0x34
            //   68????????           |                     

        $sequence_12 = { 8b0485808e4100 8b4de0 f644082801 7515 }
            // n = 4, score = 200
            //   8b0485808e4100       | mov                 eax, dword ptr [eax*4 + 0x418e80]
            //   8b4de0               | mov                 ecx, dword ptr [ebp - 0x20]
            //   f644082801           | test                byte ptr [eax + ecx + 0x28], 1
            //   7515                 | jne                 0x17

        $sequence_13 = { 8934b8 8bc7 83e03f 6bc830 8b0495808e4100 8b440818 }
            // n = 6, score = 200
            //   8934b8               | mov                 dword ptr [eax + edi*4], esi
            //   8bc7                 | mov                 eax, edi
            //   83e03f               | and                 eax, 0x3f
            //   6bc830               | imul                ecx, eax, 0x30
            //   8b0495808e4100       | mov                 eax, dword ptr [edx*4 + 0x418e80]
            //   8b440818             | mov                 eax, dword ptr [eax + ecx + 0x18]

        $sequence_14 = { 0f82eefeffff eb29 8b55d4 8a07 8b0c95808e4100 8844192e 8b0495808e4100 }
            // n = 7, score = 200
            //   0f82eefeffff         | jb                  0xfffffef4
            //   eb29                 | jmp                 0x2b
            //   8b55d4               | mov                 edx, dword ptr [ebp - 0x2c]
            //   8a07                 | mov                 al, byte ptr [edi]
            //   8b0c95808e4100       | mov                 ecx, dword ptr [edx*4 + 0x418e80]
            //   8844192e             | mov                 byte ptr [ecx + ebx + 0x2e], al
            //   8b0495808e4100       | mov                 eax, dword ptr [edx*4 + 0x418e80]

        $sequence_15 = { 8bde 895dd8 8365fc00 8b45e4 8b0485808e4100 8b4de0 }
            // n = 6, score = 200
            //   8bde                 | mov                 ebx, esi
            //   895dd8               | mov                 dword ptr [ebp - 0x28], ebx
            //   8365fc00             | and                 dword ptr [ebp - 4], 0
            //   8b45e4               | mov                 eax, dword ptr [ebp - 0x1c]
            //   8b0485808e4100       | mov                 eax, dword ptr [eax*4 + 0x418e80]
            //   8b4de0               | mov                 ecx, dword ptr [ebp - 0x20]

    condition:
        7 of them and filesize < 286720
}