rule win_mofksys_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.mofksys."
        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.mofksys"
        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 = { 6a00 68???????? 8b0f 51 8d55b4 52 ff15???????? }
            // n = 7, score = 100
            //   6a00                 | push                0
            //   68????????           |                     
            //   8b0f                 | mov                 ecx, dword ptr [edi]
            //   51                   | push                ecx
            //   8d55b4               | lea                 edx, [ebp - 0x4c]
            //   52                   | push                edx
            //   ff15????????         |                     

        $sequence_1 = { 8b426c 8b4d08 8b516c 8b4010 2b420c 0f80d40a0000 }
            // n = 6, score = 100
            //   8b426c               | mov                 eax, dword ptr [edx + 0x6c]
            //   8b4d08               | mov                 ecx, dword ptr [ebp + 8]
            //   8b516c               | mov                 edx, dword ptr [ecx + 0x6c]
            //   8b4010               | mov                 eax, dword ptr [eax + 0x10]
            //   2b420c               | sub                 eax, dword ptr [edx + 0xc]
            //   0f80d40a0000         | jo                  0xada

        $sequence_2 = { 8bd0 8d4d9c ffd3 8b559c c7459c00000000 6a03 }
            // n = 6, score = 100
            //   8bd0                 | mov                 edx, eax
            //   8d4d9c               | lea                 ecx, [ebp - 0x64]
            //   ffd3                 | call                ebx
            //   8b559c               | mov                 edx, dword ptr [ebp - 0x64]
            //   c7459c00000000       | mov                 dword ptr [ebp - 0x64], 0
            //   6a03                 | push                3

        $sequence_3 = { 8d4dc8 ff15???????? 8bd0 b9???????? ff15???????? 8d4dc8 51 }
            // n = 7, score = 100
            //   8d4dc8               | lea                 ecx, [ebp - 0x38]
            //   ff15????????         |                     
            //   8bd0                 | mov                 edx, eax
            //   b9????????           |                     
            //   ff15????????         |                     
            //   8d4dc8               | lea                 ecx, [ebp - 0x38]
            //   51                   | push                ecx

        $sequence_4 = { 8b952cffffff 6a12 81e20080ffff 66f7da 1bd2 f7da f7da }
            // n = 7, score = 100
            //   8b952cffffff         | mov                 edx, dword ptr [ebp - 0xd4]
            //   6a12                 | push                0x12
            //   81e20080ffff         | and                 edx, 0xffff8000
            //   66f7da               | neg                 dx
            //   1bd2                 | sbb                 edx, edx
            //   f7da                 | neg                 edx
            //   f7da                 | neg                 edx

        $sequence_5 = { 64892500000000 81ecd8000000 53 56 57 8965ec c745f0c02b4000 }
            // n = 7, score = 100
            //   64892500000000       | mov                 dword ptr fs:[0], esp
            //   81ecd8000000         | sub                 esp, 0xd8
            //   53                   | push                ebx
            //   56                   | push                esi
            //   57                   | push                edi
            //   8965ec               | mov                 dword ptr [ebp - 0x14], esp
            //   c745f0c02b4000       | mov                 dword ptr [ebp - 0x10], 0x402bc0

        $sequence_6 = { 8b8d50ffffff 83c10c ff15???????? 8d4dc0 ff15???????? c745fccc000000 6a01 }
            // n = 7, score = 100
            //   8b8d50ffffff         | mov                 ecx, dword ptr [ebp - 0xb0]
            //   83c10c               | add                 ecx, 0xc
            //   ff15????????         |                     
            //   8d4dc0               | lea                 ecx, [ebp - 0x40]
            //   ff15????????         |                     
            //   c745fccc000000       | mov                 dword ptr [ebp - 4], 0xcc
            //   6a01                 | push                1

        $sequence_7 = { ffd6 50 68???????? 68???????? ffd7 8bd0 8d4dbc }
            // n = 7, score = 100
            //   ffd6                 | call                esi
            //   50                   | push                eax
            //   68????????           |                     
            //   68????????           |                     
            //   ffd7                 | call                edi
            //   8bd0                 | mov                 edx, eax
            //   8d4dbc               | lea                 ecx, [ebp - 0x44]

        $sequence_8 = { c7459801000000 c7459002000000 ffd3 8bd0 8d4dd4 ffd7 8d4d90 }
            // n = 7, score = 100
            //   c7459801000000       | mov                 dword ptr [ebp - 0x68], 1
            //   c7459002000000       | mov                 dword ptr [ebp - 0x70], 2
            //   ffd3                 | call                ebx
            //   8bd0                 | mov                 edx, eax
            //   8d4dd4               | lea                 ecx, [ebp - 0x2c]
            //   ffd7                 | call                edi
            //   8d4d90               | lea                 ecx, [ebp - 0x70]

        $sequence_9 = { 8b420c 034590 50 8b4dc8 51 8b55d8 52 }
            // n = 7, score = 100
            //   8b420c               | mov                 eax, dword ptr [edx + 0xc]
            //   034590               | add                 eax, dword ptr [ebp - 0x70]
            //   50                   | push                eax
            //   8b4dc8               | mov                 ecx, dword ptr [ebp - 0x38]
            //   51                   | push                ecx
            //   8b55d8               | mov                 edx, dword ptr [ebp - 0x28]
            //   52                   | push                edx

    condition:
        7 of them and filesize < 401408
}