rule win_bolek_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.bolek."
        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.bolek"
        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 = { 897c2418 33f0 c1ca02 8bcd c1c105 03cf 03f1 }
            // n = 7, score = 600
            //   897c2418             | mov                 dword ptr [esp + 0x18], edi
            //   33f0                 | xor                 esi, eax
            //   c1ca02               | ror                 edx, 2
            //   8bcd                 | mov                 ecx, ebp
            //   c1c105               | rol                 ecx, 5
            //   03cf                 | add                 ecx, edi
            //   03f1                 | add                 esi, ecx

        $sequence_1 = { e8???????? 8d4520 50 8d45d0 50 e8???????? 8d45d0 }
            // n = 7, score = 600
            //   e8????????           |                     
            //   8d4520               | lea                 eax, [ebp + 0x20]
            //   50                   | push                eax
            //   8d45d0               | lea                 eax, [ebp - 0x30]
            //   50                   | push                eax
            //   e8????????           |                     
            //   8d45d0               | lea                 eax, [ebp - 0x30]

        $sequence_2 = { ff15???????? 85c0 7433 6a10 56 57 ff15???????? }
            // n = 7, score = 600
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax
            //   7433                 | je                  0x35
            //   6a10                 | push                0x10
            //   56                   | push                esi
            //   57                   | push                edi
            //   ff15????????         |                     

        $sequence_3 = { ff742430 8bfe 89742428 8974242c ff15???????? 8be8 83fdff }
            // n = 7, score = 600
            //   ff742430             | push                dword ptr [esp + 0x30]
            //   8bfe                 | mov                 edi, esi
            //   89742428             | mov                 dword ptr [esp + 0x28], esi
            //   8974242c             | mov                 dword ptr [esp + 0x2c], esi
            //   ff15????????         |                     
            //   8be8                 | mov                 ebp, eax
            //   83fdff               | cmp                 ebp, -1

        $sequence_4 = { 8b6c2410 3b7c2418 7f62 66ff844a3c0b0000 8364242c00 3b7c2414 7c11 }
            // n = 7, score = 600
            //   8b6c2410             | mov                 ebp, dword ptr [esp + 0x10]
            //   3b7c2418             | cmp                 edi, dword ptr [esp + 0x18]
            //   7f62                 | jg                  0x64
            //   66ff844a3c0b0000     | inc                 word ptr [edx + ecx*2 + 0xb3c]
            //   8364242c00           | and                 dword ptr [esp + 0x2c], 0
            //   3b7c2414             | cmp                 edi, dword ptr [esp + 0x14]
            //   7c11                 | jl                  0x13

        $sequence_5 = { 50 51 e8???????? 83c414 85c0 744e 6a14 }
            // n = 7, score = 600
            //   50                   | push                eax
            //   51                   | push                ecx
            //   e8????????           |                     
            //   83c414               | add                 esp, 0x14
            //   85c0                 | test                eax, eax
            //   744e                 | je                  0x50
            //   6a14                 | push                0x14

        $sequence_6 = { eb0c be170000c0 eb05 be420200c0 53 e8???????? 59 }
            // n = 7, score = 600
            //   eb0c                 | jmp                 0xe
            //   be170000c0           | mov                 esi, 0xc0000017
            //   eb05                 | jmp                 7
            //   be420200c0           | mov                 esi, 0xc0000242
            //   53                   | push                ebx
            //   e8????????           |                     
            //   59                   | pop                 ecx

        $sequence_7 = { e8???????? 6800020000 ffb424dc000000 8d4744 50 e8???????? 8b44243c }
            // n = 7, score = 600
            //   e8????????           |                     
            //   6800020000           | push                0x200
            //   ffb424dc000000       | push                dword ptr [esp + 0xdc]
            //   8d4744               | lea                 eax, [edi + 0x44]
            //   50                   | push                eax
            //   e8????????           |                     
            //   8b44243c             | mov                 eax, dword ptr [esp + 0x3c]

        $sequence_8 = { ffb42430010000 ffb42430010000 e8???????? 8bf8 83c41c 897c240c 85ff }
            // n = 7, score = 600
            //   ffb42430010000       | push                dword ptr [esp + 0x130]
            //   ffb42430010000       | push                dword ptr [esp + 0x130]
            //   e8????????           |                     
            //   8bf8                 | mov                 edi, eax
            //   83c41c               | add                 esp, 0x1c
            //   897c240c             | mov                 dword ptr [esp + 0xc], edi
            //   85ff                 | test                edi, edi

        $sequence_9 = { ff7610 e8???????? 59 59 83661400 8d4e30 e8???????? }
            // n = 7, score = 600
            //   ff7610               | push                dword ptr [esi + 0x10]
            //   e8????????           |                     
            //   59                   | pop                 ecx
            //   59                   | pop                 ecx
            //   83661400             | and                 dword ptr [esi + 0x14], 0
            //   8d4e30               | lea                 ecx, [esi + 0x30]
            //   e8????????           |                     

    condition:
        7 of them and filesize < 892928
}