rule win_scarecrow_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.scarecrow."
        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.scarecrow"
        malpedia_rule_date = "20260916"
        malpedia_hash = "53a643781c18e08f4a50949af60172d837a0b6f6"
        malpedia_version = "20260917"
        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 = { c685adfdffff37 c685aefdffff37 8a85a5fdffff 80bda4fdffff00 753a 33f6 }
            // n = 6, score = 100
            //   c685adfdffff37       | mov                 byte ptr [ebp - 0x253], 0x37
            //   c685aefdffff37       | mov                 byte ptr [ebp - 0x252], 0x37
            //   8a85a5fdffff         | mov                 al, byte ptr [ebp - 0x25b]
            //   80bda4fdffff00       | cmp                 byte ptr [ebp - 0x25c], 0
            //   753a                 | jne                 0x3c
            //   33f6                 | xor                 esi, esi

        $sequence_1 = { 83c8fc 40 7445 8b4df4 8d4303 83c102 0fafc8 }
            // n = 7, score = 100
            //   83c8fc               | or                  eax, 0xfffffffc
            //   40                   | inc                 eax
            //   7445                 | je                  0x47
            //   8b4df4               | mov                 ecx, dword ptr [ebp - 0xc]
            //   8d4303               | lea                 eax, [ebx + 3]
            //   83c102               | add                 ecx, 2
            //   0fafc8               | imul                ecx, eax

        $sequence_2 = { 752c 33c9 0f1f4000 8a840d79ffffff 0fb6c0 6bc025 83e825 }
            // n = 7, score = 100
            //   752c                 | jne                 0x2e
            //   33c9                 | xor                 ecx, ecx
            //   0f1f4000             | nop                 dword ptr [eax]
            //   8a840d79ffffff       | mov                 al, byte ptr [ebp + ecx - 0x87]
            //   0fb6c0               | movzx               eax, al
            //   6bc025               | imul                eax, eax, 0x25
            //   83e825               | sub                 eax, 0x25

        $sequence_3 = { 8d8565faffff 898550f5ffff c68540feffff00 c68541feffff11 c68542feffff13 c68543feffff72 c68544feffff13 }
            // n = 7, score = 100
            //   8d8565faffff         | lea                 eax, [ebp - 0x59b]
            //   898550f5ffff         | mov                 dword ptr [ebp - 0xab0], eax
            //   c68540feffff00       | mov                 byte ptr [ebp - 0x1c0], 0
            //   c68541feffff11       | mov                 byte ptr [ebp - 0x1bf], 0x11
            //   c68542feffff13       | mov                 byte ptr [ebp - 0x1be], 0x13
            //   c68543feffff72       | mov                 byte ptr [ebp - 0x1bd], 0x72
            //   c68544feffff13       | mov                 byte ptr [ebp - 0x1bc], 0x13

        $sequence_4 = { 51 ff5010 8bf0 c7858cf7ffff05f26700 8b858cf7ffff 99 f7fb }
            // n = 7, score = 100
            //   51                   | push                ecx
            //   ff5010               | call                dword ptr [eax + 0x10]
            //   8bf0                 | mov                 esi, eax
            //   c7858cf7ffff05f26700     | mov    dword ptr [ebp - 0x874], 0x67f205
            //   8b858cf7ffff         | mov                 eax, dword ptr [ebp - 0x874]
            //   99                   | cdq                 
            //   f7fb                 | idiv                ebx

        $sequence_5 = { c3 833b00 c785e4feffff00000000 0f8695020000 8d4314 8985e0feffff 8b30 }
            // n = 7, score = 100
            //   c3                   | ret                 
            //   833b00               | cmp                 dword ptr [ebx], 0
            //   c785e4feffff00000000     | mov    dword ptr [ebp - 0x11c], 0
            //   0f8695020000         | jbe                 0x29b
            //   8d4314               | lea                 eax, [ebx + 0x14]
            //   8985e0feffff         | mov                 dword ptr [ebp - 0x120], eax
            //   8b30                 | mov                 esi, dword ptr [eax]

        $sequence_6 = { c645c305 c645c405 8a8565ffffff 80bd64ffffff00 7534 33db be05000000 }
            // n = 7, score = 100
            //   c645c305             | mov                 byte ptr [ebp - 0x3d], 5
            //   c645c405             | mov                 byte ptr [ebp - 0x3c], 5
            //   8a8565ffffff         | mov                 al, byte ptr [ebp - 0x9b]
            //   80bd64ffffff00       | cmp                 byte ptr [ebp - 0x9c], 0
            //   7534                 | jne                 0x36
            //   33db                 | xor                 ebx, ebx
            //   be05000000           | mov                 esi, 5

        $sequence_7 = { 83e956 8bc1 c1e004 03c1 03c0 99 }
            // n = 6, score = 100
            //   83e956               | sub                 ecx, 0x56
            //   8bc1                 | mov                 eax, ecx
            //   c1e004               | shl                 eax, 4
            //   03c1                 | add                 eax, ecx
            //   03c0                 | add                 eax, eax
            //   99                   | cdq                 

        $sequence_8 = { c685ecfdffff00 c685edfdffff55 c685eefdffff64 c685effdffff06 c685f0fdffff64 c685f1fdffff45 c685f2fdffff64 }
            // n = 7, score = 100
            //   c685ecfdffff00       | mov                 byte ptr [ebp - 0x214], 0
            //   c685edfdffff55       | mov                 byte ptr [ebp - 0x213], 0x55
            //   c685eefdffff64       | mov                 byte ptr [ebp - 0x212], 0x64
            //   c685effdffff06       | mov                 byte ptr [ebp - 0x211], 6
            //   c685f0fdffff64       | mov                 byte ptr [ebp - 0x210], 0x64
            //   c685f1fdffff45       | mov                 byte ptr [ebp - 0x20f], 0x45
            //   c685f2fdffff64       | mov                 byte ptr [ebp - 0x20e], 0x64

        $sequence_9 = { 8985f8feffff c645a800 c645a94c c645aa41 c645ab34 c645ac41 c645ad03 }
            // n = 7, score = 100
            //   8985f8feffff         | mov                 dword ptr [ebp - 0x108], eax
            //   c645a800             | mov                 byte ptr [ebp - 0x58], 0
            //   c645a94c             | mov                 byte ptr [ebp - 0x57], 0x4c
            //   c645aa41             | mov                 byte ptr [ebp - 0x56], 0x41
            //   c645ab34             | mov                 byte ptr [ebp - 0x55], 0x34
            //   c645ac41             | mov                 byte ptr [ebp - 0x54], 0x41
            //   c645ad03             | mov                 byte ptr [ebp - 0x53], 3

    condition:
        7 of them and filesize < 501760
}