rule win_unidentified_013_korean_malware_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.unidentified_013_korean_malware."
        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.unidentified_013_korean_malware"
        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 = { ff15???????? 8bf0 85f6 740e 8d54240c 52 ff15???????? }
            // n = 7, score = 200
            //   ff15????????         |                     
            //   8bf0                 | mov                 esi, eax
            //   85f6                 | test                esi, esi
            //   740e                 | je                  0x10
            //   8d54240c             | lea                 edx, [esp + 0xc]
            //   52                   | push                edx
            //   ff15????????         |                     

        $sequence_1 = { 8b542408 52 e8???????? 83c404 8b8c2420070000 8bc6 }
            // n = 6, score = 200
            //   8b542408             | mov                 edx, dword ptr [esp + 8]
            //   52                   | push                edx
            //   e8????????           |                     
            //   83c404               | add                 esp, 4
            //   8b8c2420070000       | mov                 ecx, dword ptr [esp + 0x720]
            //   8bc6                 | mov                 eax, esi

        $sequence_2 = { 837c242401 0f85be000000 0fb6542e04 3bd1 7412 }
            // n = 5, score = 200
            //   837c242401           | cmp                 dword ptr [esp + 0x24], 1
            //   0f85be000000         | jne                 0xc4
            //   0fb6542e04           | movzx               edx, byte ptr [esi + ebp + 4]
            //   3bd1                 | cmp                 edx, ecx
            //   7412                 | je                  0x14

        $sequence_3 = { 40 84c9 75f9 2bc2 8d6801 8d4501 3944241c }
            // n = 7, score = 200
            //   40                   | inc                 eax
            //   84c9                 | test                cl, cl
            //   75f9                 | jne                 0xfffffffb
            //   2bc2                 | sub                 eax, edx
            //   8d6801               | lea                 ebp, [eax + 1]
            //   8d4501               | lea                 eax, [ebp + 1]
            //   3944241c             | cmp                 dword ptr [esp + 0x1c], eax

        $sequence_4 = { 83c414 6a00 6a00 6a00 8d4c2460 51 68???????? }
            // n = 7, score = 200
            //   83c414               | add                 esp, 0x14
            //   6a00                 | push                0
            //   6a00                 | push                0
            //   6a00                 | push                0
            //   8d4c2460             | lea                 ecx, [esp + 0x60]
            //   51                   | push                ecx
            //   68????????           |                     

        $sequence_5 = { 894808 80f34d 33c9 89500c 85ff 7c17 7f04 }
            // n = 7, score = 200
            //   894808               | mov                 dword ptr [eax + 8], ecx
            //   80f34d               | xor                 bl, 0x4d
            //   33c9                 | xor                 ecx, ecx
            //   89500c               | mov                 dword ptr [eax + 0xc], edx
            //   85ff                 | test                edi, edi
            //   7c17                 | jl                  0x19
            //   7f04                 | jg                  6

        $sequence_6 = { 803c337f 8944242c 0f840f010000 3bd8 0f8307010000 0fb6543301 }
            // n = 6, score = 200
            //   803c337f             | cmp                 byte ptr [ebx + esi], 0x7f
            //   8944242c             | mov                 dword ptr [esp + 0x2c], eax
            //   0f840f010000         | je                  0x115
            //   3bd8                 | cmp                 ebx, eax
            //   0f8307010000         | jae                 0x10d
            //   0fb6543301           | movzx               edx, byte ptr [ebx + esi + 1]

        $sequence_7 = { c744240c08000000 eb22 8b44241c 8d542410 52 56 }
            // n = 6, score = 200
            //   c744240c08000000     | mov                 dword ptr [esp + 0xc], 8
            //   eb22                 | jmp                 0x24
            //   8b44241c             | mov                 eax, dword ptr [esp + 0x1c]
            //   8d542410             | lea                 edx, [esp + 0x10]
            //   52                   | push                edx
            //   56                   | push                esi

        $sequence_8 = { 43 803c337f 0f85f1feffff 33ff 5b 5d 3bf7 }
            // n = 7, score = 200
            //   43                   | inc                 ebx
            //   803c337f             | cmp                 byte ptr [ebx + esi], 0x7f
            //   0f85f1feffff         | jne                 0xfffffef7
            //   33ff                 | xor                 edi, edi
            //   5b                   | pop                 ebx
            //   5d                   | pop                 ebp
            //   3bf7                 | cmp                 esi, edi

        $sequence_9 = { ff15???????? 5e 85c0 7406 881d???????? 5b }
            // n = 6, score = 200
            //   ff15????????         |                     
            //   5e                   | pop                 esi
            //   85c0                 | test                eax, eax
            //   7406                 | je                  8
            //   881d????????         |                     
            //   5b                   | pop                 ebx

    condition:
        7 of them and filesize < 204800
}