rule win_felismus_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.felismus."
        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.felismus"
        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 = { d3eb 8b0d???????? d3e0 8bce f7d1 0bd8 8b442428 }
            // n = 7, score = 100
            //   d3eb                 | shr                 ebx, cl
            //   8b0d????????         |                     
            //   d3e0                 | shl                 eax, cl
            //   8bce                 | mov                 ecx, esi
            //   f7d1                 | not                 ecx
            //   0bd8                 | or                  ebx, eax
            //   8b442428             | mov                 eax, dword ptr [esp + 0x28]

        $sequence_1 = { d3e6 8b482c 894c243c 0bd6 8bf3 03d3 }
            // n = 6, score = 100
            //   d3e6                 | shl                 esi, cl
            //   8b482c               | mov                 ecx, dword ptr [eax + 0x2c]
            //   894c243c             | mov                 dword ptr [esp + 0x3c], ecx
            //   0bd6                 | or                  edx, esi
            //   8bf3                 | mov                 esi, ebx
            //   03d3                 | add                 edx, ebx

        $sequence_2 = { 89542410 8b5110 56 2be8 57 89542420 bb01000000 }
            // n = 7, score = 100
            //   89542410             | mov                 dword ptr [esp + 0x10], edx
            //   8b5110               | mov                 edx, dword ptr [ecx + 0x10]
            //   56                   | push                esi
            //   2be8                 | sub                 ebp, eax
            //   57                   | push                edi
            //   89542420             | mov                 dword ptr [esp + 0x20], edx
            //   bb01000000           | mov                 ebx, 1

        $sequence_3 = { 46 83fe04 88040a 7ceb 43 83c704 83fb04 }
            // n = 7, score = 100
            //   46                   | inc                 esi
            //   83fe04               | cmp                 esi, 4
            //   88040a               | mov                 byte ptr [edx + ecx], al
            //   7ceb                 | jl                  0xffffffed
            //   43                   | inc                 ebx
            //   83c704               | add                 edi, 4
            //   83fb04               | cmp                 ebx, 4

        $sequence_4 = { e8???????? 83c444 6a32 e8???????? 8bf8 8b4514 }
            // n = 6, score = 100
            //   e8????????           |                     
            //   83c444               | add                 esp, 0x44
            //   6a32                 | push                0x32
            //   e8????????           |                     
            //   8bf8                 | mov                 edi, eax
            //   8b4514               | mov                 eax, dword ptr [ebp + 0x14]

        $sequence_5 = { 33c0 8bfb 895de4 f3ab eb06 8b5de4 8b7508 }
            // n = 7, score = 100
            //   33c0                 | xor                 eax, eax
            //   8bfb                 | mov                 edi, ebx
            //   895de4               | mov                 dword ptr [ebp - 0x1c], ebx
            //   f3ab                 | rep stosd           dword ptr es:[edi], eax
            //   eb06                 | jmp                 8
            //   8b5de4               | mov                 ebx, dword ptr [ebp - 0x1c]
            //   8b7508               | mov                 esi, dword ptr [ebp + 8]

        $sequence_6 = { 83e802 7469 48 7442 48 741b 8d942450040000 }
            // n = 7, score = 100
            //   83e802               | sub                 eax, 2
            //   7469                 | je                  0x6b
            //   48                   | dec                 eax
            //   7442                 | je                  0x44
            //   48                   | dec                 eax
            //   741b                 | je                  0x1d
            //   8d942450040000       | lea                 edx, [esp + 0x450]

        $sequence_7 = { 56 ffd3 83c40c eb06 8b1d???????? 6804010000 e8???????? }
            // n = 7, score = 100
            //   56                   | push                esi
            //   ffd3                 | call                ebx
            //   83c40c               | add                 esp, 0xc
            //   eb06                 | jmp                 8
            //   8b1d????????         |                     
            //   6804010000           | push                0x104
            //   e8????????           |                     

        $sequence_8 = { 6801040000 ff15???????? 8be8 83c404 }
            // n = 4, score = 100
            //   6801040000           | push                0x401
            //   ff15????????         |                     
            //   8be8                 | mov                 ebp, eax
            //   83c404               | add                 esp, 4

        $sequence_9 = { 55 53 ff15???????? 85c0 0f848e010000 6801040000 ff15???????? }
            // n = 7, score = 100
            //   55                   | push                ebp
            //   53                   | push                ebx
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax
            //   0f848e010000         | je                  0x194
            //   6801040000           | push                0x401
            //   ff15????????         |                     

    condition:
        7 of them and filesize < 204800
}