rule win_zupdax_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.zupdax."
        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.zupdax"
        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 51 e8???????? 83c418 8bc6 c3 }
            // n = 6, score = 200
            //   6a00                 | push                0
            //   51                   | push                ecx
            //   e8????????           |                     
            //   83c418               | add                 esp, 0x18
            //   8bc6                 | mov                 eax, esi
            //   c3                   | ret                 

        $sequence_1 = { 765b 53 41 81e1ff000080 7908 49 81c900ffffff }
            // n = 7, score = 200
            //   765b                 | jbe                 0x5d
            //   53                   | push                ebx
            //   41                   | inc                 ecx
            //   81e1ff000080         | and                 ecx, 0x800000ff
            //   7908                 | jns                 0xa
            //   49                   | dec                 ecx
            //   81c900ffffff         | or                  ecx, 0xffffff00

        $sequence_2 = { 895e2c e8???????? 8b460c 83c404 }
            // n = 4, score = 200
            //   895e2c               | mov                 dword ptr [esi + 0x2c], ebx
            //   e8????????           |                     
            //   8b460c               | mov                 eax, dword ptr [esi + 0xc]
            //   83c404               | add                 esp, 4

        $sequence_3 = { 68???????? ff15???????? 8d442444 83c0fe 668b4802 }
            // n = 5, score = 200
            //   68????????           |                     
            //   ff15????????         |                     
            //   8d442444             | lea                 eax, [esp + 0x44]
            //   83c0fe               | add                 eax, -2
            //   668b4802             | mov                 cx, word ptr [eax + 2]

        $sequence_4 = { 83c408 8b4618 50 895e24 }
            // n = 4, score = 200
            //   83c408               | add                 esp, 8
            //   8b4618               | mov                 eax, dword ptr [esi + 0x18]
            //   50                   | push                eax
            //   895e24               | mov                 dword ptr [esi + 0x24], ebx

        $sequence_5 = { e8???????? 8b560c 52 e8???????? 83c408 8b06 }
            // n = 6, score = 200
            //   e8????????           |                     
            //   8b560c               | mov                 edx, dword ptr [esi + 0xc]
            //   52                   | push                edx
            //   e8????????           |                     
            //   83c408               | add                 esp, 8
            //   8b06                 | mov                 eax, dword ptr [esi]

        $sequence_6 = { e8???????? 8b15???????? a1???????? 668b0d???????? }
            // n = 4, score = 200
            //   e8????????           |                     
            //   8b15????????         |                     
            //   a1????????           |                     
            //   668b0d????????       |                     

        $sequence_7 = { 33db 57 3bc3 7419 8b4c2408 8b7e28 51 }
            // n = 7, score = 200
            //   33db                 | xor                 ebx, ebx
            //   57                   | push                edi
            //   3bc3                 | cmp                 eax, ebx
            //   7419                 | je                  0x1b
            //   8b4c2408             | mov                 ecx, dword ptr [esp + 8]
            //   8b7e28               | mov                 edi, dword ptr [esi + 0x28]
            //   51                   | push                ecx

        $sequence_8 = { 43 0fb61403 30142f 47 3b7c2418 72a7 }
            // n = 6, score = 200
            //   43                   | inc                 ebx
            //   0fb61403             | movzx               edx, byte ptr [ebx + eax]
            //   30142f               | xor                 byte ptr [edi + ebp], dl
            //   47                   | inc                 edi
            //   3b7c2418             | cmp                 edi, dword ptr [esp + 0x18]
            //   72a7                 | jb                  0xffffffa9

        $sequence_9 = { 51 8b4624 53 33db 57 3bc3 7419 }
            // n = 7, score = 200
            //   51                   | push                ecx
            //   8b4624               | mov                 eax, dword ptr [esi + 0x24]
            //   53                   | push                ebx
            //   33db                 | xor                 ebx, ebx
            //   57                   | push                edi
            //   3bc3                 | cmp                 eax, ebx
            //   7419                 | je                  0x1b

    condition:
        7 of them and filesize < 1032192
}