rule win_fakeword_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.fakeword."
        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.fakeword"
        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 = { 4f 89442430 3bc7 0f8654ffffff 5f 8bc3 }
            // n = 6, score = 200
            //   4f                   | dec                 edi
            //   89442430             | mov                 dword ptr [esp + 0x30], eax
            //   3bc7                 | cmp                 eax, edi
            //   0f8654ffffff         | jbe                 0xffffff5a
            //   5f                   | pop                 edi
            //   8bc3                 | mov                 eax, ebx

        $sequence_1 = { 6880000000 50 ff15???????? f644242810 }
            // n = 4, score = 200
            //   6880000000           | push                0x80
            //   50                   | push                eax
            //   ff15????????         |                     
            //   f644242810           | test                byte ptr [esp + 0x28], 0x10

        $sequence_2 = { 8d8d48eeffff 8d9548deffff 51 52 e8???????? 83c408 a1???????? }
            // n = 7, score = 200
            //   8d8d48eeffff         | lea                 ecx, [ebp - 0x11b8]
            //   8d9548deffff         | lea                 edx, [ebp - 0x21b8]
            //   51                   | push                ecx
            //   52                   | push                edx
            //   e8????????           |                     
            //   83c408               | add                 esp, 8
            //   a1????????           |                     

        $sequence_3 = { 81c484000000 c3 6800000002 6a00 6a01 ff15???????? 8bf0 }
            // n = 7, score = 200
            //   81c484000000         | add                 esp, 0x84
            //   c3                   | ret                 
            //   6800000002           | push                0x2000000
            //   6a00                 | push                0
            //   6a01                 | push                1
            //   ff15????????         |                     
            //   8bf0                 | mov                 esi, eax

        $sequence_4 = { 8bf1 81e200000020 81e600000040 81e100000080 85d2 7408 808c045401000001 }
            // n = 7, score = 200
            //   8bf1                 | mov                 esi, ecx
            //   81e200000020         | and                 edx, 0x20000000
            //   81e600000040         | and                 esi, 0x40000000
            //   81e100000080         | and                 ecx, 0x80000000
            //   85d2                 | test                edx, edx
            //   7408                 | je                  0xa
            //   808c045401000001     | or                  byte ptr [esp + eax + 0x154], 1

        $sequence_5 = { 6a02 6a00 6800f005ff 57 ffd6 6a02 6a00 }
            // n = 7, score = 200
            //   6a02                 | push                2
            //   6a00                 | push                0
            //   6800f005ff           | push                0xff05f000
            //   57                   | push                edi
            //   ffd6                 | call                esi
            //   6a02                 | push                2
            //   6a00                 | push                0

        $sequence_6 = { ff15???????? 8b4c2410 8d44242c 50 51 ff15???????? 85c0 }
            // n = 7, score = 200
            //   ff15????????         |                     
            //   8b4c2410             | mov                 ecx, dword ptr [esp + 0x10]
            //   8d44242c             | lea                 eax, [esp + 0x2c]
            //   50                   | push                eax
            //   51                   | push                ecx
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax

        $sequence_7 = { 50 55 8d7704 6a51 68???????? 56 }
            // n = 6, score = 200
            //   50                   | push                eax
            //   55                   | push                ebp
            //   8d7704               | lea                 esi, [edi + 4]
            //   6a51                 | push                0x51
            //   68????????           |                     
            //   56                   | push                esi

        $sequence_8 = { 83c43c 3bfb 7606 5f 5e 33c0 5b }
            // n = 7, score = 200
            //   83c43c               | add                 esp, 0x3c
            //   3bfb                 | cmp                 edi, ebx
            //   7606                 | jbe                 8
            //   5f                   | pop                 edi
            //   5e                   | pop                 esi
            //   33c0                 | xor                 eax, eax
            //   5b                   | pop                 ebx

        $sequence_9 = { 8a0c0f 81e1ff000000 c1e104 33c1 33c9 8a4c3a02 c1e004 }
            // n = 7, score = 200
            //   8a0c0f               | mov                 cl, byte ptr [edi + ecx]
            //   81e1ff000000         | and                 ecx, 0xff
            //   c1e104               | shl                 ecx, 4
            //   33c1                 | xor                 eax, ecx
            //   33c9                 | xor                 ecx, ecx
            //   8a4c3a02             | mov                 cl, byte ptr [edx + edi + 2]
            //   c1e004               | shl                 eax, 4

    condition:
        7 of them and filesize < 98304
}