rule win_meltingclaw_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        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 = "20260422"
        malpedia_hash = "a182e35da64e6d71cb55f125c4d4225196523f14"
        malpedia_version = "20260504"
        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 = { 0f8484000000 ffc1 4c63e1 498bcc e8???????? }
            // n = 5, score = 200
            //   0f8484000000         | dec                 eax
            //   ffc1                 | test                eax, eax
            //   4c63e1               | je                  0x432
            //   498bcc               | dec                 esp
            //   e8????????           |                     

        $sequence_1 = { 4c8b0a 33f6 448bc6 48c7420816000000 4c8bd2 48c7421009000000 488bf9 }
            // n = 7, score = 200
            //   4c8b0a               | mov                 dword ptr [ecx + 0x1c], eax
            //   33f6                 | int3                
            //   448bc6               | xor                 eax, eax
            //   48c7420816000000     | dec                 esp
            //   4c8bd2               | lea                 ebx, [0xffff589b]
            //   48c7421009000000     | mov                 byte ptr [ecx + 0x18], al
            //   488bf9               | xorps               xmm0, xmm0

        $sequence_2 = { f3420f7f4409e0 f3420f7f4401f0 f30f7f00 c3 488bc4 }
            // n = 5, score = 200
            //   f3420f7f4409e0       | inc                 eax
            //   f3420f7f4401f0       | mov                 bh, 1
            //   f30f7f00             | dec                 eax
            //   c3                   | lea                 ecx, [0x1972a]
            //   488bc4               | dec                 eax

        $sequence_3 = { 33d2 41b880000000 8b5820 e8???????? }
            // n = 4, score = 200
            //   33d2                 | movzx               ecx, word ptr [esp + eax*2 + 0x20]
            //   41b880000000         | inc                 bx
            //   8b5820               | mov                 dword ptr [esi + eax*2], ecx
            //   e8????????           |                     

        $sequence_4 = { 23d1 03c2 448bf8 23c1 41c1ff0c 2bc2 }
            // n = 6, score = 200
            //   23d1                 | inc                 ecx
            //   03c2                 | dec                 eax
            //   448bf8               | cmp                 ecx, 8
            //   23c1                 | jb                  0x44d
            //   41c1ff0c             | dec                 eax
            //   2bc2                 | div                 dword ptr [edi]

        $sequence_5 = { 33c0 0f11442450 6689442460 0f104118 }
            // n = 4, score = 200
            //   33c0                 | mov                 esi, dword ptr [esi + esi*8 + 0x1b1e0]
            //   0f11442450           | xor                 edx, edx
            //   6689442460           | jne                 0x148
            //   0f104118             | dec                 ebp

        $sequence_6 = { 0fb6c0 0fb74c4420 6643890c46 49ffc0 4983f80e 72b0 488b8c2420020000 }
            // n = 7, score = 200
            //   0fb6c0               | lea                 ebx, [0x18ee3]
            //   0fb74c4420           | inc                 ecx
            //   6643890c46           | mov                 eax, 0x104
            //   49ffc0               | dec                 eax
            //   4983f80e             | mov                 edx, ebx
            //   72b0                 | xor                 ecx, ecx
            //   488b8c2420020000     | dec                 eax

        $sequence_7 = { 750e 48396928 7508 48396930 b001 7403 }
            // n = 6, score = 200
            //   750e                 | dec                 eax
            //   48396928             | mov                 dword ptr [ebp + 0x390], eax
            //   7508                 | xor                 edx, edx
            //   48396930             | dec                 eax
            //   b001                 | lea                 ecx, [ebp + 0x180]
            //   7403                 | inc                 ecx

        $sequence_8 = { 4983f80f 0f870c010000 666666660f1f840000000000 478b8c8200800200 4d03ca }
            // n = 5, score = 200
            //   4983f80f             | inc                 edx
            //   0f870c010000         | mov                 cl, byte ptr [ecx + eax + 0x19650]
            //   666666660f1f840000000000     | dec    eax
            //   478b8c8200800200     | sub                 edx, eax
            //   4d03ca               | mov                 eax, dword ptr [edx - 4]

        $sequence_9 = { 4833c4 4889442470 488bda 488bf9 4889542428 }
            // n = 5, score = 200
            //   4833c4               | dec                 eax
            //   4889442470           | lea                 eax, [0x14a16]
            //   488bda               | jne                 0x133d
            //   488bf9               | dec                 eax
            //   4889542428           | mov                 eax, edi

    condition:
        7 of them and filesize < 348160
}