rule win_data_exfiltrator_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.data_exfiltrator."
        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.data_exfiltrator"
        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 = { 4839842480000000 7610 488b842480000000 4889842488000000 }
            // n = 4, score = 100
            //   4839842480000000     | mov                 ecx, eax
            //   7610                 | inc                 ecx
            //   488b842480000000     | mov                 ecx, 0x8000
            //   4889842488000000     | dec                 esp

        $sequence_1 = { 7407 837c244000 7502 eb33 8b442440 }
            // n = 5, score = 100
            //   7407                 | sub                 esp, 0xb8
            //   837c244000           | mov                 dword ptr [esp + 0x20], 0
            //   7502                 | xor                 edx, edx
            //   eb33                 | dec                 eax
            //   8b442440             | mov                 eax, dword ptr [esp + 0xd0]

        $sequence_2 = { 4889842498000000 8b442458 48898424a8000000 488b842488000000 48898424a0000000 488b8c2488010000 e8???????? }
            // n = 7, score = 100
            //   4889842498000000     | dec                 eax
            //   8b442458             | mov                 edx, dword ptr [esp + 0x48]
            //   48898424a8000000     | dec                 eax
            //   488b842488000000     | mov                 ecx, eax
            //   48898424a0000000     | dec                 eax
            //   488b8c2488010000     | test                eax, eax
            //   e8????????           |                     

        $sequence_3 = { 4889442438 488b4c2438 e8???????? 448bc0 488b542438 488b4c2430 e8???????? }
            // n = 7, score = 100
            //   4889442438           | mov                 dword ptr [eax + 0x58], ecx
            //   488b4c2438           | dec                 eax
            //   e8????????           |                     
            //   448bc0               | mov                 eax, dword ptr [esp + 0x30]
            //   488b542438           | dec                 eax
            //   488b4c2430           | mov                 ecx, dword ptr [esp + 0x130]
            //   e8????????           |                     

        $sequence_4 = { c644244d78 c644244e7a c644244f62 c644245075 }
            // n = 4, score = 100
            //   c644244d78           | dec                 eax
            //   c644244e7a           | mov                 ecx, dword ptr [esp + 0x68]
            //   c644244f62           | dec                 eax
            //   c644245075           | add                 ecx, eax

        $sequence_5 = { 488b442418 4883c002 4889442418 488b442448 4883c002 4889442448 }
            // n = 6, score = 100
            //   488b442418           | mov                 edx, dword ptr [esp + 0x30]
            //   4883c002             | dec                 eax
            //   4889442418           | lea                 ecx, [esp + 0x40]
            //   488b442448           | mov                 eax, dword ptr [eax + 0x4018]
            //   4883c002             | dec                 eax
            //   4889442448           | mov                 eax, dword ptr [esp + 0x60]

        $sequence_6 = { c6442460fb c6442461fc c6442462fe c6442463ff }
            // n = 4, score = 100
            //   c6442460fb           | mov                 eax, dword ptr [ecx + 0x50]
            //   c6442461fc           | xor                 edx, edx
            //   c6442462fe           | dec                 eax
            //   c6442463ff           | mov                 ecx, eax

        $sequence_7 = { 4889542410 48894c2408 4881ecf8000000 48c744243000000000 48c784248800000000000000 48c744245800000000 }
            // n = 6, score = 100
            //   4889542410           | mov                 eax, dword ptr [eax + 0x38]
            //   48894c2408           | mov                 dword ptr [esp + 0x34], eax
            //   4881ecf8000000       | cmp                 dword ptr [esp + 0x34], 0
            //   48c744243000000000     | jle    0x1bb7
            //   48c784248800000000000000     | dec    eax
            //   48c744245800000000     | arpl    word ptr [esp + 0x34], ax

        $sequence_8 = { 83e830 89442428 837c242800 7c3a 8b442448 39442428 7d30 }
            // n = 7, score = 100
            //   83e830               | dec                 eax
            //   89442428             | mov                 ecx, dword ptr [esp + 0x40]
            //   837c242800           | mov                 ecx, 0x18
            //   7c3a                 | rep movsb           byte ptr es:[edi], byte ptr [esi]
            //   8b442448             | dec                 eax
            //   39442428             | mov                 eax, dword ptr [esp + 0x90]
            //   7d30                 | mov                 eax, dword ptr [esp + 0x60]

        $sequence_9 = { 488b4c2440 ff15???????? 4889442420 488d152b530000 488b4c2440 ff15???????? }
            // n = 6, score = 100
            //   488b4c2440           | mov                 byte ptr [esp + 0x33], 0x6d
            //   ff15????????         |                     
            //   4889442420           | mov                 byte ptr [esp + 0x30], 0x63
            //   488d152b530000       | mov                 byte ptr [esp + 0x31], 0
            //   488b4c2440           | mov                 byte ptr [esp + 0x32], 7
            //   ff15????????         |                     

    condition:
        7 of them and filesize < 107520
}