rule win_meltingclaw_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.meltingclaw."
        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.meltingclaw"
        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 = { 4c8d8554010000 488bc8 418d511b ff15???????? }
            // n = 4, score = 200
            //   4c8d8554010000       | dec                 eax
            //   488bc8               | mov                 dword ptr [ecx + 8], eax
            //   418d511b             | dec                 eax
            //   ff15????????         |                     

        $sequence_1 = { 0f104928 0f114c2440 488d542430 488d4c2450 e8???????? 488bf5 }
            // n = 6, score = 200
            //   0f104928             | mov                 dword ptr [esp + 0x30], esp
            //   0f114c2440           | dec                 eax
            //   488d542430           | lea                 ecx, [esp + 0x20]
            //   488d4c2450           | dec                 esp
            //   e8????????           |                     
            //   488bf5               | mov                 dword ptr [esp + 0x38], ebp

        $sequence_2 = { 7e58 4c8d4c2440 488bcf 413bdf 751f 488364242000 458bc6 }
            // n = 7, score = 200
            //   7e58                 | inc                 ebp
            //   4c8d4c2440           | lea                 edi, [esp + 1]
            //   488bcf               | inc                 ebp
            //   413bdf               | cmp                 esi, edi
            //   751f                 | jl                  0xb0f
            //   488364242000         | mov                 edi, dword ptr [ebp + 0x144]
            //   458bc6               | dec                 eax

        $sequence_3 = { 72af 488bc3 488b8c2430010000 4833cc e8???????? 488b9c2470010000 4881c440010000 }
            // n = 7, score = 200
            //   72af                 | inc                 ecx
            //   488bc3               | mov                 eax, dword ptr [edi + eax*8 + 0x1bd90]
            //   488b8c2430010000     | jmp                 0xba4
            //   4833cc               | dec                 eax
            //   e8????????           |                     
            //   488b9c2470010000     | mov                 dword ptr [esp + 8], ebx
            //   4881c440010000       | dec                 eax

        $sequence_4 = { 488b542468 be00100000 4883fa10 722e }
            // n = 4, score = 200
            //   488b542468           | dec                 eax
            //   be00100000           | lea                 eax, [0x140cd]
            //   4883fa10             | dec                 eax
            //   722e                 | and                 dword ptr [edx + 0x10], 0

        $sequence_5 = { d3e8 4d894108 41894118 410fb608 83e10f 4a0fbe841940960100 428a8c1950960100 }
            // n = 7, score = 200
            //   d3e8                 | sub                 esp, 0x30
            //   4d894108             | dec                 eax
            //   41894118             | mov                 dword ptr [esp + 0x20], 0xfffffffe
            //   410fb608             | mov                 ebx, ecx
            //   83e10f               | dec                 eax
            //   4a0fbe841940960100     | and    dword ptr [esp + 0x48], 0
            //   428a8c1950960100     | dec                 esp

        $sequence_6 = { e8???????? eb55 498bd0 498bc9 }
            // n = 4, score = 200
            //   e8????????           |                     
            //   eb55                 | movapd              xmm2, xmm1
            //   498bd0               | dec                 esp
            //   498bc9               | lea                 ecx, [0xf194]

        $sequence_7 = { e8???????? 0f1087e8000000 0f11442430 0f108ff8000000 0f114c2440 488d542430 488d4c2450 }
            // n = 7, score = 200
            //   e8????????           |                     
            //   0f1087e8000000       | lea                 eax, [0xb245]
            //   0f11442430           | inc                 ecx
            //   0f108ff8000000       | mov                 ecx, 0x1b
            //   0f114c2440           | dec                 eax
            //   488d542430           | mov                 dword ptr [esp + 0x20], eax
            //   488d4c2450           | dec                 eax

        $sequence_8 = { 4c8be8 4533ff 83a54001000000 488d9540010000 488bcb 41ffd5 8b8d40010000 }
            // n = 7, score = 200
            //   4c8be8               | dec                 eax
            //   4533ff               | mov                 ecx, dword ptr [esp + 0x220]
            //   83a54001000000       | movzx               eax, al
            //   488d9540010000       | movzx               ecx, word ptr [esp + eax*2 + 0x20]
            //   488bcb               | inc                 bx
            //   41ffd5               | mov                 dword ptr [esi + eax*2], ecx
            //   8b8d40010000         | dec                 ecx

        $sequence_9 = { 458be1 488d8d20010000 488985b0000000 4489ad40010000 458bf8 44898d44010000 }
            // n = 6, score = 200
            //   458be1               | dec                 ecx
            //   488d8d20010000       | mov                 esp, ebx
            //   488985b0000000       | dec                 esp
            //   4489ad40010000       | lea                 ebx, [esp + 0x11b0]
            //   458bf8               | dec                 ecx
            //   44898d44010000       | mov                 ebx, dword ptr [ebx + 0x28]

    condition:
        7 of them and filesize < 348160
}