rule win_purplewave_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.purplewave."
        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.purplewave"
        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 = { 8bf1 8b7d08 8bc7 2b06 99 6a28 59 }
            // n = 7, score = 400
            //   8bf1                 | mov                 esi, ecx
            //   8b7d08               | mov                 edi, dword ptr [ebp + 8]
            //   8bc7                 | mov                 eax, edi
            //   2b06                 | sub                 eax, dword ptr [esi]
            //   99                   | cdq                 
            //   6a28                 | push                0x28
            //   59                   | pop                 ecx

        $sequence_1 = { 8b45a0 50 8b08 ff5108 ff15???????? 68???????? }
            // n = 6, score = 400
            //   8b45a0               | mov                 eax, dword ptr [ebp - 0x60]
            //   50                   | push                eax
            //   8b08                 | mov                 ecx, dword ptr [eax]
            //   ff5108               | call                dword ptr [ecx + 8]
            //   ff15????????         |                     
            //   68????????           |                     

        $sequence_2 = { e8???????? ff7508 8d4dd0 c645fc01 e8???????? }
            // n = 5, score = 400
            //   e8????????           |                     
            //   ff7508               | push                dword ptr [ebp + 8]
            //   8d4dd0               | lea                 ecx, [ebp - 0x30]
            //   c645fc01             | mov                 byte ptr [ebp - 4], 1
            //   e8????????           |                     

        $sequence_3 = { e8???????? c20800 55 8bec 81ec18020000 a1???????? 33c5 }
            // n = 7, score = 400
            //   e8????????           |                     
            //   c20800               | ret                 8
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp
            //   81ec18020000         | sub                 esp, 0x218
            //   a1????????           |                     
            //   33c5                 | xor                 eax, ebp

        $sequence_4 = { e8???????? 895e3c 8bc6 895e40 895e44 895e48 895e4c }
            // n = 7, score = 400
            //   e8????????           |                     
            //   895e3c               | mov                 dword ptr [esi + 0x3c], ebx
            //   8bc6                 | mov                 eax, esi
            //   895e40               | mov                 dword ptr [esi + 0x40], ebx
            //   895e44               | mov                 dword ptr [esi + 0x44], ebx
            //   895e48               | mov                 dword ptr [esi + 0x48], ebx
            //   895e4c               | mov                 dword ptr [esi + 0x4c], ebx

        $sequence_5 = { ff5108 8b4d94 85c9 0f8506feffff 8d45a4 8bcf 50 }
            // n = 7, score = 400
            //   ff5108               | call                dword ptr [ecx + 8]
            //   8b4d94               | mov                 ecx, dword ptr [ebp - 0x6c]
            //   85c9                 | test                ecx, ecx
            //   0f8506feffff         | jne                 0xfffffe0c
            //   8d45a4               | lea                 eax, [ebp - 0x5c]
            //   8bcf                 | mov                 ecx, edi
            //   50                   | push                eax

        $sequence_6 = { 8bc1 eb03 83c8ff 8b4dfc 5f 5e 33cd }
            // n = 7, score = 400
            //   8bc1                 | mov                 eax, ecx
            //   eb03                 | jmp                 5
            //   83c8ff               | or                  eax, 0xffffffff
            //   8b4dfc               | mov                 ecx, dword ptr [ebp - 4]
            //   5f                   | pop                 edi
            //   5e                   | pop                 esi
            //   33cd                 | xor                 ecx, ebp

        $sequence_7 = { 85c0 7528 8bce e8???????? 8b5640 8b7644 8b4df4 }
            // n = 7, score = 400
            //   85c0                 | test                eax, eax
            //   7528                 | jne                 0x2a
            //   8bce                 | mov                 ecx, esi
            //   e8????????           |                     
            //   8b5640               | mov                 edx, dword ptr [esi + 0x40]
            //   8b7644               | mov                 esi, dword ptr [esi + 0x44]
            //   8b4df4               | mov                 ecx, dword ptr [ebp - 0xc]

        $sequence_8 = { 59 c645fc44 0bdf 83781410 899d3cffffff 7202 8b00 }
            // n = 7, score = 400
            //   59                   | pop                 ecx
            //   c645fc44             | mov                 byte ptr [ebp - 4], 0x44
            //   0bdf                 | or                  ebx, edi
            //   83781410             | cmp                 dword ptr [eax + 0x14], 0x10
            //   899d3cffffff         | mov                 dword ptr [ebp - 0xc4], ebx
            //   7202                 | jb                  4
            //   8b00                 | mov                 eax, dword ptr [eax]

        $sequence_9 = { 8bf7 6a06 59 8bfa f3a5 83601000 8bfa }
            // n = 7, score = 400
            //   8bf7                 | mov                 esi, edi
            //   6a06                 | push                6
            //   59                   | pop                 ecx
            //   8bfa                 | mov                 edi, edx
            //   f3a5                 | rep movsd           dword ptr es:[edi], dword ptr [esi]
            //   83601000             | and                 dword ptr [eax + 0x10], 0
            //   8bfa                 | mov                 edi, edx

    condition:
        7 of them and filesize < 1400832
}