rule win_heloag_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.heloag."
        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.heloag"
        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 = { 6a00 68???????? 51 6a00 ff15???????? 5f 5e }
            // n = 7, score = 100
            //   6a00                 | push                0
            //   68????????           |                     
            //   51                   | push                ecx
            //   6a00                 | push                0
            //   ff15????????         |                     
            //   5f                   | pop                 edi
            //   5e                   | pop                 esi

        $sequence_1 = { 0f8481000000 eb62 83f801 755d 8d4c2410 55 }
            // n = 6, score = 100
            //   0f8481000000         | je                  0x87
            //   eb62                 | jmp                 0x64
            //   83f801               | cmp                 eax, 1
            //   755d                 | jne                 0x5f
            //   8d4c2410             | lea                 ecx, [esp + 0x10]
            //   55                   | push                ebp

        $sequence_2 = { 83c404 8b442418 8b4c2414 83c104 895c2420 8b400c 895c2424 }
            // n = 7, score = 100
            //   83c404               | add                 esp, 4
            //   8b442418             | mov                 eax, dword ptr [esp + 0x18]
            //   8b4c2414             | mov                 ecx, dword ptr [esp + 0x14]
            //   83c104               | add                 ecx, 4
            //   895c2420             | mov                 dword ptr [esp + 0x20], ebx
            //   8b400c               | mov                 eax, dword ptr [eax + 0xc]
            //   895c2424             | mov                 dword ptr [esp + 0x24], ebx

        $sequence_3 = { 3bf3 0f849b000000 8a44240f 8a54240f c706???????? 8d4e20 885e04 }
            // n = 7, score = 100
            //   3bf3                 | cmp                 esi, ebx
            //   0f849b000000         | je                  0xa1
            //   8a44240f             | mov                 al, byte ptr [esp + 0xf]
            //   8a54240f             | mov                 dl, byte ptr [esp + 0xf]
            //   c706????????         |                     
            //   8d4e20               | lea                 ecx, [esi + 0x20]
            //   885e04               | mov                 byte ptr [esi + 4], bl

        $sequence_4 = { 6a01 68???????? ffd7 56 6a05 8d542448 6a01 }
            // n = 7, score = 100
            //   6a01                 | push                1
            //   68????????           |                     
            //   ffd7                 | call                edi
            //   56                   | push                esi
            //   6a05                 | push                5
            //   8d542448             | lea                 edx, [esp + 0x48]
            //   6a01                 | push                1

        $sequence_5 = { 64892500000000 81ec1c010000 8a442413 53 56 57 6a00 }
            // n = 7, score = 100
            //   64892500000000       | mov                 dword ptr fs:[0], esp
            //   81ec1c010000         | sub                 esp, 0x11c
            //   8a442413             | mov                 al, byte ptr [esp + 0x13]
            //   53                   | push                ebx
            //   56                   | push                esi
            //   57                   | push                edi
            //   6a00                 | push                0

        $sequence_6 = { c684245c40000002 eb02 33ed b900100000 33c0 8d7c2454 f3ab }
            // n = 7, score = 100
            //   c684245c40000002     | mov                 byte ptr [esp + 0x405c], 2
            //   eb02                 | jmp                 4
            //   33ed                 | xor                 ebp, ebp
            //   b900100000           | mov                 ecx, 0x1000
            //   33c0                 | xor                 eax, eax
            //   8d7c2454             | lea                 edi, [esp + 0x54]
            //   f3ab                 | rep stosd           dword ptr es:[edi], eax

        $sequence_7 = { 8b08 50 ff5108 8b4d08 8b45e8 885dfc 3bc3 }
            // n = 7, score = 100
            //   8b08                 | mov                 ecx, dword ptr [eax]
            //   50                   | push                eax
            //   ff5108               | call                dword ptr [ecx + 8]
            //   8b4d08               | mov                 ecx, dword ptr [ebp + 8]
            //   8b45e8               | mov                 eax, dword ptr [ebp - 0x18]
            //   885dfc               | mov                 byte ptr [ebp - 4], bl
            //   3bc3                 | cmp                 eax, ebx

        $sequence_8 = { 89570c 8a48ff fec1 8848ff eb42 6a01 53 }
            // n = 7, score = 100
            //   89570c               | mov                 dword ptr [edi + 0xc], edx
            //   8a48ff               | mov                 cl, byte ptr [eax - 1]
            //   fec1                 | inc                 cl
            //   8848ff               | mov                 byte ptr [eax - 1], cl
            //   eb42                 | jmp                 0x44
            //   6a01                 | push                1
            //   53                   | push                ebx

        $sequence_9 = { 8b8c2424010000 33f6 66ab aa 8d442418 83c107 50 }
            // n = 7, score = 100
            //   8b8c2424010000       | mov                 ecx, dword ptr [esp + 0x124]
            //   33f6                 | xor                 esi, esi
            //   66ab                 | stosw               word ptr es:[edi], ax
            //   aa                   | stosb               byte ptr es:[edi], al
            //   8d442418             | lea                 eax, [esp + 0x18]
            //   83c107               | add                 ecx, 7
            //   50                   | push                eax

    condition:
        7 of them and filesize < 401408
}