rule win_nvisospit_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.nvisospit."
        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.nvisospit"
        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 = { 0f8e16010000 85d2 0f8493010000 b9???????? 81f9???????? 7384 }
            // n = 6, score = 100
            //   0f8e16010000         | jle                 0x11c
            //   85d2                 | test                edx, edx
            //   0f8493010000         | je                  0x199
            //   b9????????           |                     
            //   81f9????????         |                     
            //   7384                 | jae                 0xffffff86

        $sequence_1 = { 8d95a2f9ffff 89542420 8d95a4f9ffff 8954241c 8d95acfbffff 89542418 }
            // n = 6, score = 100
            //   8d95a2f9ffff         | lea                 edx, [ebp - 0x65e]
            //   89542420             | mov                 dword ptr [esp + 0x20], edx
            //   8d95a4f9ffff         | lea                 edx, [ebp - 0x65c]
            //   8954241c             | mov                 dword ptr [esp + 0x1c], edx
            //   8d95acfbffff         | lea                 edx, [ebp - 0x454]
            //   89542418             | mov                 dword ptr [esp + 0x18], edx

        $sequence_2 = { 8d1c76 c1e302 01d8 897808 c70000000000 }
            // n = 5, score = 100
            //   8d1c76               | lea                 ebx, [esi + esi*2]
            //   c1e302               | shl                 ebx, 2
            //   01d8                 | add                 eax, ebx
            //   897808               | mov                 dword ptr [eax + 8], edi
            //   c70000000000         | mov                 dword ptr [eax], 0

        $sequence_3 = { 8b8000004000 83fb10 8db900004000 8945c4 0f849d000000 83fb20 }
            // n = 6, score = 100
            //   8b8000004000         | mov                 eax, dword ptr [eax + 0x400000]
            //   83fb10               | cmp                 ebx, 0x10
            //   8db900004000         | lea                 edi, [ecx + 0x400000]
            //   8945c4               | mov                 dword ptr [ebp - 0x3c], eax
            //   0f849d000000         | je                  0xa3
            //   83fb20               | cmp                 ebx, 0x20

        $sequence_4 = { 8b7104 85f6 0f85dffeffff 8b4108 }
            // n = 4, score = 100
            //   8b7104               | mov                 esi, dword ptr [ecx + 4]
            //   85f6                 | test                esi, esi
            //   0f85dffeffff         | jne                 0xfffffee5
            //   8b4108               | mov                 eax, dword ptr [ecx + 8]

        $sequence_5 = { 8d9da4f9ffff 81c307010000 895c2414 8d9da4f9ffff }
            // n = 4, score = 100
            //   8d9da4f9ffff         | lea                 ebx, [ebp - 0x65c]
            //   81c307010000         | add                 ebx, 0x107
            //   895c2414             | mov                 dword ptr [esp + 0x14], ebx
            //   8d9da4f9ffff         | lea                 ebx, [ebp - 0x65c]

        $sequence_6 = { 8b55d4 8954240c c7442408???????? c744240400000000 890424 }
            // n = 5, score = 100
            //   8b55d4               | mov                 edx, dword ptr [ebp - 0x2c]
            //   8954240c             | mov                 dword ptr [esp + 0xc], edx
            //   c7442408????????     |                     
            //   c744240400000000     | mov                 dword ptr [esp + 4], 0
            //   890424               | mov                 dword ptr [esp], eax

        $sequence_7 = { c78594f9ffff01000000 66c78592f9ffff0000 c6857df9ffff4d c6857ef9ffff4d c6857ff9ffff4b 8b45dc }
            // n = 6, score = 100
            //   c78594f9ffff01000000     | mov    dword ptr [ebp - 0x66c], 1
            //   66c78592f9ffff0000     | mov    word ptr [ebp - 0x66e], 0
            //   c6857df9ffff4d       | mov                 byte ptr [ebp - 0x683], 0x4d
            //   c6857ef9ffff4d       | mov                 byte ptr [ebp - 0x682], 0x4d
            //   c6857ff9ffff4b       | mov                 byte ptr [ebp - 0x681], 0x4b
            //   8b45dc               | mov                 eax, dword ptr [ebp - 0x24]

        $sequence_8 = { 81c307010000 895c2414 8d9da4f9ffff 83c306 895c2410 894c240c 89542408 }
            // n = 7, score = 100
            //   81c307010000         | add                 ebx, 0x107
            //   895c2414             | mov                 dword ptr [esp + 0x14], ebx
            //   8d9da4f9ffff         | lea                 ebx, [ebp - 0x65c]
            //   83c306               | add                 ebx, 6
            //   895c2410             | mov                 dword ptr [esp + 0x10], ebx
            //   894c240c             | mov                 dword ptr [esp + 0xc], ecx
            //   89542408             | mov                 dword ptr [esp + 8], edx

        $sequence_9 = { ffd0 83ec04 c70424???????? e8???????? 8b4304 }
            // n = 5, score = 100
            //   ffd0                 | call                eax
            //   83ec04               | sub                 esp, 4
            //   c70424????????       |                     
            //   e8????????           |                     
            //   8b4304               | mov                 eax, dword ptr [ebx + 4]

    condition:
        7 of them and filesize < 66560
}