rule win_nightdoor_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.nightdoor."
        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.nightdoor"
        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 = { 8bd9 c1eb08 81e3ff000000 0fb69bb0e20710 33f3 8b5d08 81e3ff000000 }
            // n = 7, score = 100
            //   8bd9                 | mov                 ebx, ecx
            //   c1eb08               | shr                 ebx, 8
            //   81e3ff000000         | and                 ebx, 0xff
            //   0fb69bb0e20710       | movzx               ebx, byte ptr [ebx + 0x1007e2b0]
            //   33f3                 | xor                 esi, ebx
            //   8b5d08               | mov                 ebx, dword ptr [ebp + 8]
            //   81e3ff000000         | and                 ebx, 0xff

        $sequence_1 = { c645fc05 e8???????? 8d8df0feffff c645fc01 e8???????? 8d75b4 8d8d9cfeffff }
            // n = 7, score = 100
            //   c645fc05             | mov                 byte ptr [ebp - 4], 5
            //   e8????????           |                     
            //   8d8df0feffff         | lea                 ecx, [ebp - 0x110]
            //   c645fc01             | mov                 byte ptr [ebp - 4], 1
            //   e8????????           |                     
            //   8d75b4               | lea                 esi, [ebp - 0x4c]
            //   8d8d9cfeffff         | lea                 ecx, [ebp - 0x164]

        $sequence_2 = { c745f400000000 8b4d18 833900 743e 8b55ec 8b4220 83c001 }
            // n = 7, score = 100
            //   c745f400000000       | mov                 dword ptr [ebp - 0xc], 0
            //   8b4d18               | mov                 ecx, dword ptr [ebp + 0x18]
            //   833900               | cmp                 dword ptr [ecx], 0
            //   743e                 | je                  0x40
            //   8b55ec               | mov                 edx, dword ptr [ebp - 0x14]
            //   8b4220               | mov                 eax, dword ptr [edx + 0x20]
            //   83c001               | add                 eax, 1

        $sequence_3 = { c68537ffffff01 c645fc05 8d8d40ffffff e8???????? c645fc04 8d8d5fffffff e8???????? }
            // n = 7, score = 100
            //   c68537ffffff01       | mov                 byte ptr [ebp - 0xc9], 1
            //   c645fc05             | mov                 byte ptr [ebp - 4], 5
            //   8d8d40ffffff         | lea                 ecx, [ebp - 0xc0]
            //   e8????????           |                     
            //   c645fc04             | mov                 byte ptr [ebp - 4], 4
            //   8d8d5fffffff         | lea                 ecx, [ebp - 0xa1]
            //   e8????????           |                     

        $sequence_4 = { e8???????? 83c40c 8d4d18 e8???????? 50 68???????? }
            // n = 6, score = 100
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc
            //   8d4d18               | lea                 ecx, [ebp + 0x18]
            //   e8????????           |                     
            //   50                   | push                eax
            //   68????????           |                     

        $sequence_5 = { 8916 894a08 e9???????? 8b12 385a10 751c c6411001 }
            // n = 7, score = 100
            //   8916                 | mov                 dword ptr [esi], edx
            //   894a08               | mov                 dword ptr [edx + 8], ecx
            //   e9????????           |                     
            //   8b12                 | mov                 edx, dword ptr [edx]
            //   385a10               | cmp                 byte ptr [edx + 0x10], bl
            //   751c                 | jne                 0x1e
            //   c6411001             | mov                 byte ptr [ecx + 0x10], 1

        $sequence_6 = { 56 8d4df0 897df0 e8???????? 8b4df4 8b45f0 3bc8 }
            // n = 7, score = 100
            //   56                   | push                esi
            //   8d4df0               | lea                 ecx, [ebp - 0x10]
            //   897df0               | mov                 dword ptr [ebp - 0x10], edi
            //   e8????????           |                     
            //   8b4df4               | mov                 ecx, dword ptr [ebp - 0xc]
            //   8b45f0               | mov                 eax, dword ptr [ebp - 0x10]
            //   3bc8                 | cmp                 ecx, eax

        $sequence_7 = { 6a00 53 8bce e8???????? 8bc3 5f 8be5 }
            // n = 7, score = 100
            //   6a00                 | push                0
            //   53                   | push                ebx
            //   8bce                 | mov                 ecx, esi
            //   e8????????           |                     
            //   8bc3                 | mov                 eax, ebx
            //   5f                   | pop                 edi
            //   8be5                 | mov                 esp, ebp

        $sequence_8 = { 8b442430 83c40c 57 50 53 e8???????? 83c40c }
            // n = 7, score = 100
            //   8b442430             | mov                 eax, dword ptr [esp + 0x30]
            //   83c40c               | add                 esp, 0xc
            //   57                   | push                edi
            //   50                   | push                eax
            //   53                   | push                ebx
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc

        $sequence_9 = { 894b60 8b8eac000000 6a00 e8???????? 50 8b8548feffff 53 }
            // n = 7, score = 100
            //   894b60               | mov                 dword ptr [ebx + 0x60], ecx
            //   8b8eac000000         | mov                 ecx, dword ptr [esi + 0xac]
            //   6a00                 | push                0
            //   e8????????           |                     
            //   50                   | push                eax
            //   8b8548feffff         | mov                 eax, dword ptr [ebp - 0x1b8]
            //   53                   | push                ebx

    condition:
        7 of them and filesize < 1124352
}