rule win_doublefinger_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.doublefinger."
        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.doublefinger"
        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 = { 8b442404 8b0c24 03c8 8bc1 03442408 8bc0 }
            // n = 6, score = 100
            //   8b442404             | dec                 eax
            //   8b0c24               | mov                 dword ptr [esp + 0x20], edx
            //   03c8                 | dec                 esp
            //   8bc1                 | mov                 ecx, ecx
            //   03442408             | dec                 eax
            //   8bc0                 | lea                 ecx, [0x2b32]

        $sequence_1 = { 8b442448 39442444 7d27 41b87a000000 ba61000000 488b8c2468010000 e8???????? }
            // n = 7, score = 100
            //   8b442448             | jmp                 0x1c6a
            //   39442444             | mov                 eax, dword ptr [esp + 0x64]
            //   7d27                 | inc                 eax
            //   41b87a000000         | mov                 dword ptr [esp + 0x64], eax
            //   ba61000000           | mov                 eax, dword ptr [esp + 0x70]
            //   488b8c2468010000     | add                 eax, 4
            //   e8????????           |                     

        $sequence_2 = { 4533c0 8b942464010000 488b4c2450 e8???????? }
            // n = 4, score = 100
            //   4533c0               | inc                 ebp
            //   8b942464010000       | xor                 eax, eax
            //   488b4c2450           | dec                 eax
            //   e8????????           |                     

        $sequence_3 = { 4883ec38 ba08000000 488d4c2420 e8???????? 6944244810270000 }
            // n = 5, score = 100
            //   4883ec38             | dec                 eax
            //   ba08000000           | lea                 ecx, [esp + 0xc0]
            //   488d4c2420           | call                dword ptr [eax + 0x38]
            //   e8????????           |                     
            //   6944244810270000     | dec                 eax

        $sequence_4 = { 488b4c2450 e8???????? 48898424f8020000 8b442458 35beaeaeab }
            // n = 5, score = 100
            //   488b4c2450           | dec                 eax
            //   e8????????           |                     
            //   48898424f8020000     | mov                 edx, dword ptr [esp + 0x40]
            //   8b442458             | mov                 cx, 2
            //   35beaeaeab           | dec                 eax

        $sequence_5 = { 4c89442418 4889542410 48894c2408 4883ec68 48c744243000000000 c744242880000000 c744242003000000 }
            // n = 7, score = 100
            //   4c89442418           | jae                 0x254
            //   4889542410           | mov                 byte ptr [esp], 0
            //   48894c2408           | mov                 dword ptr [esp + 4], 0
            //   4883ec68             | jmp                 0x1d8
            //   48c744243000000000     | mov    eax, ecx
            //   c744242880000000     | cmp                 eax, dword ptr [esp + 0x28]
            //   c744242003000000     | jbe                 0x209

        $sequence_6 = { 488bc1 eb7a 837c242000 7471 }
            // n = 4, score = 100
            //   488bc1               | mov                 dword ptr [esp + 0x2d0], eax
            //   eb7a                 | inc                 ebp
            //   837c242000           | xor                 eax, eax
            //   7471                 | mov                 edx, 0xeae447bb

        $sequence_7 = { 85c0 752d 41b975020000 4533c0 48c7c2ffffffff 488d8c2410030000 }
            // n = 6, score = 100
            //   85c0                 | xor                 edx, edx
            //   752d                 | test                eax, eax
            //   41b975020000         | jne                 0x19ad
            //   4533c0               | xor                 edx, edx
            //   48c7c2ffffffff       | mov                 edx, 0x3ee
            //   488d8c2410030000     | dec                 eax

        $sequence_8 = { 3565708005 8984246c010000 8b84246c010000 8b4c2460 33c8 }
            // n = 5, score = 100
            //   3565708005           | lea                 eax, [ecx + eax*2]
            //   8984246c010000       | dec                 eax
            //   8b84246c010000       | sub                 eax, dword ptr [esp + 0x30]
            //   8b4c2460             | mov                 eax, dword ptr [esp + 0x2c]
            //   33c8                 | mov                 dword ptr [esp + 0x24], eax

        $sequence_9 = { 488b8424a0020000 8b4c2460 3908 7502 }
            // n = 4, score = 100
            //   488b8424a0020000     | inc                 ebp
            //   8b4c2460             | xor                 eax, eax
            //   3908                 | mov                 edx, 0x2e5251ca
            //   7502                 | dec                 eax

    condition:
        7 of them and filesize < 115712
}