rule win_ncctrojan_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.ncctrojan."
        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.ncctrojan"
        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 = { 7536 8b85e8feffff 85c0 750a 68???????? e9???????? }
            // n = 6, score = 500
            //   7536                 | jne                 0x38
            //   8b85e8feffff         | mov                 eax, dword ptr [ebp - 0x118]
            //   85c0                 | test                eax, eax
            //   750a                 | jne                 0xc
            //   68????????           |                     
            //   e9????????           |                     

        $sequence_1 = { 68???????? e9???????? 83f801 750a 68???????? }
            // n = 5, score = 500
            //   68????????           |                     
            //   e9????????           |                     
            //   83f801               | cmp                 eax, 1
            //   750a                 | jne                 0xc
            //   68????????           |                     

        $sequence_2 = { 1bc0 83c801 85c0 0f8437040000 f644241010 8d44243c }
            // n = 6, score = 400
            //   1bc0                 | sbb                 eax, eax
            //   83c801               | or                  eax, 1
            //   85c0                 | test                eax, eax
            //   0f8437040000         | je                  0x43d
            //   f644241010           | test                byte ptr [esp + 0x10], 0x10
            //   8d44243c             | lea                 eax, [esp + 0x3c]

        $sequence_3 = { 8d85c4bfffff 50 8d85c07fffff 6800400000 50 e8???????? 83c40c }
            // n = 7, score = 400
            //   8d85c4bfffff         | lea                 eax, [ebp - 0x403c]
            //   50                   | push                eax
            //   8d85c07fffff         | lea                 eax, [ebp - 0x8040]
            //   6800400000           | push                0x4000
            //   50                   | push                eax
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc

        $sequence_4 = { 8b4c240c 8d5102 0f1f00 668b01 83c102 }
            // n = 5, score = 400
            //   8b4c240c             | mov                 ecx, dword ptr [esp + 0xc]
            //   8d5102               | lea                 edx, [ecx + 2]
            //   0f1f00               | nop                 dword ptr [eax]
            //   668b01               | mov                 ax, word ptr [ecx]
            //   83c102               | add                 ecx, 2

        $sequence_5 = { 8d45e4 8d4e01 51 6a14 }
            // n = 4, score = 400
            //   8d45e4               | lea                 eax, [ebp - 0x1c]
            //   8d4e01               | lea                 ecx, [esi + 1]
            //   51                   | push                ecx
            //   6a14                 | push                0x14

        $sequence_6 = { 83c102 6685c0 75f5 2bca d1f9 6683bc4deafdffff5c }
            // n = 6, score = 400
            //   83c102               | add                 ecx, 2
            //   6685c0               | test                ax, ax
            //   75f5                 | jne                 0xfffffff7
            //   2bca                 | sub                 ecx, edx
            //   d1f9                 | sar                 ecx, 1
            //   6683bc4deafdffff5c     | cmp    word ptr [ebp + ecx*2 - 0x216], 0x5c

        $sequence_7 = { e8???????? 68???????? 8d85e8adffff 6800400000 50 e8???????? 83c440 }
            // n = 7, score = 400
            //   e8????????           |                     
            //   68????????           |                     
            //   8d85e8adffff         | lea                 eax, [ebp - 0x5218]
            //   6800400000           | push                0x4000
            //   50                   | push                eax
            //   e8????????           |                     
            //   83c440               | add                 esp, 0x40

        $sequence_8 = { 85d2 7e10 8ac1 02c9 2480 }
            // n = 5, score = 300
            //   85d2                 | test                edx, edx
            //   7e10                 | jle                 0x12
            //   8ac1                 | mov                 al, cl
            //   02c9                 | add                 cl, cl
            //   2480                 | and                 al, 0x80

        $sequence_9 = { 6a00 50 c645fc02 e8???????? 8945e4 83c40c }
            // n = 6, score = 300
            //   6a00                 | push                0
            //   50                   | push                eax
            //   c645fc02             | mov                 byte ptr [ebp - 4], 2
            //   e8????????           |                     
            //   8945e4               | mov                 dword ptr [ebp - 0x1c], eax
            //   83c40c               | add                 esp, 0xc

        $sequence_10 = { 85db 0f84b8000000 6a14 59 }
            // n = 4, score = 300
            //   85db                 | test                ebx, ebx
            //   0f84b8000000         | je                  0xbe
            //   6a14                 | push                0x14
            //   59                   | pop                 ecx

        $sequence_11 = { 8b542408 8d420c 8b8a2cf8ffff 33c8 e8???????? 8b4afc }
            // n = 6, score = 300
            //   8b542408             | mov                 edx, dword ptr [esp + 8]
            //   8d420c               | lea                 eax, [edx + 0xc]
            //   8b8a2cf8ffff         | mov                 ecx, dword ptr [edx - 0x7d4]
            //   33c8                 | xor                 ecx, eax
            //   e8????????           |                     
            //   8b4afc               | mov                 ecx, dword ptr [edx - 4]

        $sequence_12 = { 8b542408 8d420c 8b8a0cfefeff 33c8 }
            // n = 4, score = 300
            //   8b542408             | mov                 edx, dword ptr [esp + 8]
            //   8d420c               | lea                 eax, [edx + 0xc]
            //   8b8a0cfefeff         | mov                 ecx, dword ptr [edx - 0x101f4]
            //   33c8                 | xor                 ecx, eax

        $sequence_13 = { 50 e8???????? 8b4d08 e8???????? e9???????? 83ec18 }
            // n = 6, score = 300
            //   50                   | push                eax
            //   e8????????           |                     
            //   8b4d08               | mov                 ecx, dword ptr [ebp + 8]
            //   e8????????           |                     
            //   e9????????           |                     
            //   83ec18               | sub                 esp, 0x18

        $sequence_14 = { 6a00 50 e8???????? 0fb745b8 }
            // n = 4, score = 300
            //   6a00                 | push                0
            //   50                   | push                eax
            //   e8????????           |                     
            //   0fb745b8             | movzx               eax, word ptr [ebp - 0x48]

        $sequence_15 = { 55 8bec ff7508 e8???????? cc 6a00 }
            // n = 6, score = 300
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp
            //   ff7508               | push                dword ptr [ebp + 8]
            //   e8????????           |                     
            //   cc                   | int3                
            //   6a00                 | push                0

    condition:
        7 of them and filesize < 1160192
}