rule win_artra_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.artra."
        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.artra"
        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 = { 5d 5b 8b442410 5f 5e 83c41c c21000 }
            // n = 7, score = 800
            //   5d                   | pop                 ebp
            //   5b                   | pop                 ebx
            //   8b442410             | mov                 eax, dword ptr [esp + 0x10]
            //   5f                   | pop                 edi
            //   5e                   | pop                 esi
            //   83c41c               | add                 esp, 0x1c
            //   c21000               | ret                 0x10

        $sequence_1 = { 5f 8a08 40 84c9 75f9 2bc2 880c30 }
            // n = 7, score = 800
            //   5f                   | pop                 edi
            //   8a08                 | mov                 cl, byte ptr [eax]
            //   40                   | inc                 eax
            //   84c9                 | test                cl, cl
            //   75f9                 | jne                 0xfffffffb
            //   2bc2                 | sub                 eax, edx
            //   880c30               | mov                 byte ptr [eax + esi], cl

        $sequence_2 = { 83c41c c21000 5f 33c0 }
            // n = 4, score = 800
            //   83c41c               | add                 esp, 0x1c
            //   c21000               | ret                 0x10
            //   5f                   | pop                 edi
            //   33c0                 | xor                 eax, eax

        $sequence_3 = { 51 8bc6 57 33c9 8d7801 8da42400000000 }
            // n = 6, score = 800
            //   51                   | push                ecx
            //   8bc6                 | mov                 eax, esi
            //   57                   | push                edi
            //   33c9                 | xor                 ecx, ecx
            //   8d7801               | lea                 edi, [eax + 1]
            //   8da42400000000       | lea                 esp, [esp]

        $sequence_4 = { 2bc7 3bc8 72e3 8bc6 8d5001 5f }
            // n = 6, score = 800
            //   2bc7                 | sub                 eax, edi
            //   3bc8                 | cmp                 ecx, eax
            //   72e3                 | jb                  0xffffffe5
            //   8bc6                 | mov                 eax, esi
            //   8d5001               | lea                 edx, [eax + 1]
            //   5f                   | pop                 edi

        $sequence_5 = { 800431f3 8bc6 41 8d7801 8d9b00000000 8a10 }
            // n = 6, score = 800
            //   800431f3             | add                 byte ptr [ecx + esi], 0xf3
            //   8bc6                 | mov                 eax, esi
            //   41                   | inc                 ecx
            //   8d7801               | lea                 edi, [eax + 1]
            //   8d9b00000000         | lea                 ebx, [ebx]
            //   8a10                 | mov                 dl, byte ptr [eax]

        $sequence_6 = { 55 8b2d???????? 90 8b542410 }
            // n = 4, score = 600
            //   55                   | push                ebp
            //   8b2d????????         |                     
            //   90                   | nop                 
            //   8b542410             | mov                 edx, dword ptr [esp + 0x10]

        $sequence_7 = { 68???????? e8???????? 6a03 68???????? 6800040000 }
            // n = 5, score = 600
            //   68????????           |                     
            //   e8????????           |                     
            //   6a03                 | push                3
            //   68????????           |                     
            //   6800040000           | push                0x400

        $sequence_8 = { 8bf0 e8???????? 8b3d???????? 6a00 6a00 6a00 8d442414 }
            // n = 7, score = 600
            //   8bf0                 | mov                 esi, eax
            //   e8????????           |                     
            //   8b3d????????         |                     
            //   6a00                 | push                0
            //   6a00                 | push                0
            //   6a00                 | push                0
            //   8d442414             | lea                 eax, [esp + 0x14]

        $sequence_9 = { 8d442414 50 ffd7 85c0 7445 53 }
            // n = 6, score = 600
            //   8d442414             | lea                 eax, [esp + 0x14]
            //   50                   | push                eax
            //   ffd7                 | call                edi
            //   85c0                 | test                eax, eax
            //   7445                 | je                  0x47
            //   53                   | push                ebx

        $sequence_10 = { 40 42 84c9 75f6 e8???????? }
            // n = 5, score = 600
            //   40                   | inc                 eax
            //   42                   | inc                 edx
            //   84c9                 | test                cl, cl
            //   75f6                 | jne                 0xfffffff8
            //   e8????????           |                     

        $sequence_11 = { 6a00 8935???????? ff15???????? 8bf8 85ff 0f8488000000 }
            // n = 6, score = 600
            //   6a00                 | push                0
            //   8935????????         |                     
            //   ff15????????         |                     
            //   8bf8                 | mov                 edi, eax
            //   85ff                 | test                edi, edi
            //   0f8488000000         | je                  0x8e

        $sequence_12 = { 85c0 7445 53 8b1d???????? 55 8b2d???????? }
            // n = 6, score = 600
            //   85c0                 | test                eax, eax
            //   7445                 | je                  0x47
            //   53                   | push                ebx
            //   8b1d????????         |                     
            //   55                   | push                ebp
            //   8b2d????????         |                     

        $sequence_13 = { 85c9 742f 8b4234 8b30 03f1 }
            // n = 5, score = 600
            //   85c9                 | test                ecx, ecx
            //   742f                 | je                  0x31
            //   8b4234               | mov                 eax, dword ptr [edx + 0x34]
            //   8b30                 | mov                 esi, dword ptr [eax]
            //   03f1                 | add                 esi, ecx

        $sequence_14 = { 2bc2 03fb 8a4f01 47 84c9 75f8 }
            // n = 6, score = 600
            //   2bc2                 | sub                 eax, edx
            //   03fb                 | add                 edi, ebx
            //   8a4f01               | mov                 cl, byte ptr [edi + 1]
            //   47                   | inc                 edi
            //   84c9                 | test                cl, cl
            //   75f8                 | jne                 0xfffffffa

        $sequence_15 = { 85ff 0f8488000000 6a00 57 }
            // n = 4, score = 600
            //   85ff                 | test                edi, edi
            //   0f8488000000         | je                  0x8e
            //   6a00                 | push                0
            //   57                   | push                edi

        $sequence_16 = { 8d942484010000 52 6800040000 68???????? }
            // n = 4, score = 600
            //   8d942484010000       | lea                 edx, [esp + 0x184]
            //   52                   | push                edx
            //   6800040000           | push                0x400
            //   68????????           |                     

        $sequence_17 = { 8be5 5d c20400 8d4c2414 e8???????? 8b4c2434 }
            // n = 6, score = 600
            //   8be5                 | mov                 esp, ebp
            //   5d                   | pop                 ebp
            //   c20400               | ret                 4
            //   8d4c2414             | lea                 ecx, [esp + 0x14]
            //   e8????????           |                     
            //   8b4c2434             | mov                 ecx, dword ptr [esp + 0x34]

        $sequence_18 = { 8bc8 c1f905 8bf0 83e61f 8d3c8de03b4100 8b0f }
            // n = 6, score = 400
            //   8bc8                 | mov                 ecx, eax
            //   c1f905               | sar                 ecx, 5
            //   8bf0                 | mov                 esi, eax
            //   83e61f               | and                 esi, 0x1f
            //   8d3c8de03b4100       | lea                 edi, [ecx*4 + 0x413be0]
            //   8b0f                 | mov                 ecx, dword ptr [edi]

        $sequence_19 = { 83e01f c1f905 c1e006 03048de03b4100 eb02 8bc2 }
            // n = 6, score = 400
            //   83e01f               | and                 eax, 0x1f
            //   c1f905               | sar                 ecx, 5
            //   c1e006               | shl                 eax, 6
            //   03048de03b4100       | add                 eax, dword ptr [ecx*4 + 0x413be0]
            //   eb02                 | jmp                 4
            //   8bc2                 | mov                 eax, edx

        $sequence_20 = { c1e006 030495e03b4100 eb05 b8???????? f6400420 7414 }
            // n = 6, score = 400
            //   c1e006               | shl                 eax, 6
            //   030495e03b4100       | add                 eax, dword ptr [edx*4 + 0x413be0]
            //   eb05                 | jmp                 7
            //   b8????????           |                     
            //   f6400420             | test                byte ptr [eax + 4], 0x20
            //   7414                 | je                  0x16

        $sequence_21 = { 8da42400000000 8a140f fec2 8811 41 }
            // n = 5, score = 400
            //   8da42400000000       | lea                 esp, [esp]
            //   8a140f               | mov                 dl, byte ptr [edi + ecx]
            //   fec2                 | inc                 dl
            //   8811                 | mov                 byte ptr [ecx], dl
            //   41                   | inc                 ecx

        $sequence_22 = { ffd6 85c0 75cc 5d 5b }
            // n = 5, score = 400
            //   ffd6                 | call                esi
            //   85c0                 | test                eax, eax
            //   75cc                 | jne                 0xffffffce
            //   5d                   | pop                 ebp
            //   5b                   | pop                 ebx

        $sequence_23 = { c74424306d000000 c744243478364000 ffd6 8d4c2404 51 89442434 }
            // n = 6, score = 200
            //   c74424306d000000     | mov                 dword ptr [esp + 0x30], 0x6d
            //   c744243478364000     | mov                 dword ptr [esp + 0x34], 0x403678
            //   ffd6                 | call                esi
            //   8d4c2404             | lea                 ecx, [esp + 4]
            //   51                   | push                ecx
            //   89442434             | mov                 dword ptr [esp + 0x34], eax

        $sequence_24 = { 6a00 68???????? 6801000080 ff15???????? 8d4c2428 }
            // n = 5, score = 200
            //   6a00                 | push                0
            //   68????????           |                     
            //   6801000080           | push                0x80000001
            //   ff15????????         |                     
            //   8d4c2428             | lea                 ecx, [esp + 0x28]

        $sequence_25 = { 50 c744240c30000000 c744241003000000 c744241430124000 c744241800000000 c744241c00000000 89442420 }
            // n = 7, score = 200
            //   50                   | push                eax
            //   c744240c30000000     | mov                 dword ptr [esp + 0xc], 0x30
            //   c744241003000000     | mov                 dword ptr [esp + 0x10], 3
            //   c744241430124000     | mov                 dword ptr [esp + 0x14], 0x401230
            //   c744241800000000     | mov                 dword ptr [esp + 0x18], 0
            //   c744241c00000000     | mov                 dword ptr [esp + 0x1c], 0
            //   89442420             | mov                 dword ptr [esp + 0x20], eax

    condition:
        7 of them and filesize < 811008
}