rule win_ismdoor_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2023-12-06"
        version = "1"
        description = "Detects win.ismdoor."
        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.ismdoor"
        malpedia_rule_date = "20231130"
        malpedia_hash = "fc8a0e9f343f6d6ded9e7df1a64dac0cc68d7351"
        malpedia_version = "20230808"
        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 = { 83f8ff 7504 32c0 eb05 c0e804 2401 84c0 }
            // n = 7, score = 400
            //   83f8ff               | cmp                 eax, -1
            //   7504                 | jne                 6
            //   32c0                 | xor                 al, al
            //   eb05                 | jmp                 7
            //   c0e804               | shr                 al, 4
            //   2401                 | and                 al, 1
            //   84c0                 | test                al, al

        $sequence_1 = { 90 48897c2428 488d4da0 48894c2420 4c8d4d80 4c8bc3 }
            // n = 6, score = 300
            //   90                   | nop                 
            //   48897c2428           | dec                 eax
            //   488d4da0             | mov                 dword ptr [esp + 0x28], edi
            //   48894c2420           | dec                 eax
            //   4c8d4d80             | lea                 ecx, [ebp - 0x60]
            //   4c8bc3               | dec                 eax

        $sequence_2 = { 7405 488b00 ebdd 48894500 }
            // n = 4, score = 300
            //   7405                 | mov                 dword ptr [esp + 0x20], ecx
            //   488b00               | dec                 esp
            //   ebdd                 | lea                 ecx, [ebp - 0x80]
            //   48894500             | dec                 esp

        $sequence_3 = { 89442420 48c7411807000000 48894110 668901 c744242001000000 }
            // n = 5, score = 300
            //   89442420             | mov                 eax, ebx
            //   48c7411807000000     | je                  7
            //   48894110             | dec                 eax
            //   668901               | mov                 eax, dword ptr [eax]
            //   c744242001000000     | jmp                 0xffffffe2

        $sequence_4 = { 7613 498d4970 418bc2 41ffc2 }
            // n = 4, score = 300
            //   7613                 | dec                 eax
            //   498d4970             | mov                 dword ptr [ebp], eax
            //   418bc2               | mov                 dword ptr [esp + 0x20], eax
            //   41ffc2               | dec                 eax

        $sequence_5 = { 41ffc7 0f1f4000 418b16 488d4d38 e8???????? }
            // n = 5, score = 300
            //   41ffc7               | mov                 dword ptr [ecx + 0x18], 7
            //   0f1f4000             | dec                 eax
            //   418b16               | mov                 dword ptr [ecx + 0x10], eax
            //   488d4d38             | mov                 word ptr [ecx], ax
            //   e8????????           |                     

        $sequence_6 = { 8bd8 33c9 ff15???????? 488bc8 }
            // n = 4, score = 300
            //   8bd8                 | inc                 ecx
            //   33c9                 | mov                 eax, edx
            //   ff15????????         |                     
            //   488bc8               | inc                 ecx

        $sequence_7 = { 488bd6 488bcf ff5030 488bc8 }
            // n = 4, score = 300
            //   488bd6               | mov                 dword ptr [esp + 0x20], 1
            //   488bcf               | jbe                 0x15
            //   ff5030               | dec                 ecx
            //   488bc8               | lea                 ecx, [ecx + 0x70]

        $sequence_8 = { 884c0dd8 41 83f910 7cf6 }
            // n = 4, score = 100
            //   884c0dd8             | mov                 byte ptr [ebp + ecx - 0x28], cl
            //   41                   | inc                 ecx
            //   83f910               | cmp                 ecx, 0x10
            //   7cf6                 | jl                  0xfffffff8

        $sequence_9 = { 83f802 7506 c6473c00 eb04 40 }
            // n = 5, score = 100
            //   83f802               | cmp                 eax, 2
            //   7506                 | jne                 8
            //   c6473c00             | mov                 byte ptr [edi + 0x3c], 0
            //   eb04                 | jmp                 6
            //   40                   | inc                 eax

        $sequence_10 = { 8b4804 83b9ec97480000 0f94c0 8845e4 c745fc01000000 }
            // n = 5, score = 100
            //   8b4804               | mov                 ecx, dword ptr [eax + 4]
            //   83b9ec97480000       | cmp                 dword ptr [ecx + 0x4897ec], 0
            //   0f94c0               | sete                al
            //   8845e4               | mov                 byte ptr [ebp - 0x1c], al
            //   c745fc01000000       | mov                 dword ptr [ebp - 4], 1

        $sequence_11 = { c745f804000000 57 8a68fe 8d4004 8a48fb 8a78fc }
            // n = 6, score = 100
            //   c745f804000000       | mov                 dword ptr [ebp - 8], 4
            //   57                   | push                edi
            //   8a68fe               | mov                 ch, byte ptr [eax - 2]
            //   8d4004               | lea                 eax, [eax + 4]
            //   8a48fb               | mov                 cl, byte ptr [eax - 5]
            //   8a78fc               | mov                 bh, byte ptr [eax - 4]

        $sequence_12 = { 886dff 81e61f000080 7905 4e 83cee0 46 }
            // n = 6, score = 100
            //   886dff               | mov                 byte ptr [ebp - 1], ch
            //   81e61f000080         | and                 esi, 0x8000001f
            //   7905                 | jns                 7
            //   4e                   | dec                 esi
            //   83cee0               | or                  esi, 0xffffffe0
            //   46                   | inc                 esi

        $sequence_13 = { e8???????? 83c404 c744246c0f000000 c744246800000000 c644245800 837c243c08 }
            // n = 6, score = 100
            //   e8????????           |                     
            //   83c404               | add                 esp, 4
            //   c744246c0f000000     | mov                 dword ptr [esp + 0x6c], 0xf
            //   c744246800000000     | mov                 dword ptr [esp + 0x68], 0
            //   c644245800           | mov                 byte ptr [esp + 0x58], 0
            //   837c243c08           | cmp                 dword ptr [esp + 0x3c], 8

        $sequence_14 = { 75f2 8b7d10 8b07 3bf0 7421 8b4f04 }
            // n = 6, score = 100
            //   75f2                 | jne                 0xfffffff4
            //   8b7d10               | mov                 edi, dword ptr [ebp + 0x10]
            //   8b07                 | mov                 eax, dword ptr [edi]
            //   3bf0                 | cmp                 esi, eax
            //   7421                 | je                  0x23
            //   8b4f04               | mov                 ecx, dword ptr [edi + 4]

    condition:
        7 of them and filesize < 1933312
}

rule win_ismdoor_w0 {
	meta:
        author = "Florian Roth"
        reference = "https://goo.gl/urp4CD"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.ismdoor"
        malpedia_version = "20180301"
        malpedia_license = "CC BY-NC-SA 4.0"
        malpedia_sharing = "TLP:WHITE"
    strings:
        $x1 = "cmd /u /c WMIC /Node:localhost /Namespace:\\\\root\\SecurityCenter" fullword ascii
        $x2 = "cmd /a /c net user administrator /domain >>" fullword ascii
        $x3 = "cmd /a /c netstat -ant >>\"%localappdata%\\Microsoft\\" fullword ascii
        $o1 = "========================== (Net User) ==========================" ascii fullword
    condition:
        1 of them
}