rule win_fengine_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.fengine."
        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.fengine"
        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 = { 47 83c628 897dfc 3bf8 7d19 8b7df4 }
            // n = 6, score = 100
            //   47                   | inc                 edi
            //   83c628               | add                 esi, 0x28
            //   897dfc               | mov                 dword ptr [ebp - 4], edi
            //   3bf8                 | cmp                 edi, eax
            //   7d19                 | jge                 0x1b
            //   8b7df4               | mov                 edi, dword ptr [ebp - 0xc]

        $sequence_1 = { 8b852ce5ffff 8b048560514100 ff3406 ff15???????? 85c0 }
            // n = 5, score = 100
            //   8b852ce5ffff         | mov                 eax, dword ptr [ebp - 0x1ad4]
            //   8b048560514100       | mov                 eax, dword ptr [eax*4 + 0x415160]
            //   ff3406               | push                dword ptr [esi + eax]
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax

        $sequence_2 = { c7472470314000 c7472880314000 c7472ca0314000 c7473400000000 8b85bcfeffff }
            // n = 5, score = 100
            //   c7472470314000       | mov                 dword ptr [edi + 0x24], 0x403170
            //   c7472880314000       | mov                 dword ptr [edi + 0x28], 0x403180
            //   c7472ca0314000       | mov                 dword ptr [edi + 0x2c], 0x4031a0
            //   c7473400000000       | mov                 dword ptr [edi + 0x34], 0
            //   8b85bcfeffff         | mov                 eax, dword ptr [ebp - 0x144]

        $sequence_3 = { e8???????? 8b0d???????? ba01000000 85c0 0f45ca 68???????? 53 }
            // n = 7, score = 100
            //   e8????????           |                     
            //   8b0d????????         |                     
            //   ba01000000           | mov                 edx, 1
            //   85c0                 | test                eax, eax
            //   0f45ca               | cmovne              ecx, edx
            //   68????????           |                     
            //   53                   | push                ebx

        $sequence_4 = { e9???????? 6a10 68???????? e8???????? 6a07 e8???????? }
            // n = 6, score = 100
            //   e9????????           |                     
            //   6a10                 | push                0x10
            //   68????????           |                     
            //   e8????????           |                     
            //   6a07                 | push                7
            //   e8????????           |                     

        $sequence_5 = { 53 8d4e04 6800080000 51 }
            // n = 4, score = 100
            //   53                   | push                ebx
            //   8d4e04               | lea                 ecx, [esi + 4]
            //   6800080000           | push                0x800
            //   51                   | push                ecx

        $sequence_6 = { 7424 8b45ec 03f0 85c0 7413 6a00 6a00 }
            // n = 7, score = 100
            //   7424                 | je                  0x26
            //   8b45ec               | mov                 eax, dword ptr [ebp - 0x14]
            //   03f0                 | add                 esi, eax
            //   85c0                 | test                eax, eax
            //   7413                 | je                  0x15
            //   6a00                 | push                0
            //   6a00                 | push                0

        $sequence_7 = { 7473 8b85f4efffff 85c0 7469 8d3c30 81ffe8030000 7749 }
            // n = 7, score = 100
            //   7473                 | je                  0x75
            //   8b85f4efffff         | mov                 eax, dword ptr [ebp - 0x100c]
            //   85c0                 | test                eax, eax
            //   7469                 | je                  0x6b
            //   8d3c30               | lea                 edi, [eax + esi]
            //   81ffe8030000         | cmp                 edi, 0x3e8
            //   7749                 | ja                  0x4b

        $sequence_8 = { 85c0 747a 56 8b35???????? }
            // n = 4, score = 100
            //   85c0                 | test                eax, eax
            //   747a                 | je                  0x7c
            //   56                   | push                esi
            //   8b35????????         |                     

        $sequence_9 = { 53 8b5d08 56 57 6824010000 33f6 8d85d0faffff }
            // n = 7, score = 100
            //   53                   | push                ebx
            //   8b5d08               | mov                 ebx, dword ptr [ebp + 8]
            //   56                   | push                esi
            //   57                   | push                edi
            //   6824010000           | push                0x124
            //   33f6                 | xor                 esi, esi
            //   8d85d0faffff         | lea                 eax, [ebp - 0x530]

    condition:
        7 of them and filesize < 210944
}