rule win_deltastealer_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.deltastealer."
        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.deltastealer"
        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 = { 5e c3 488b01 488b4908 488b4918 48f7da 486bd218 }
            // n = 7, score = 200
            //   5e                   | lea                 eax, [0xa9d93]
            //   c3                   | dec                 eax
            //   488b01               | mov                 ecx, esi
            //   488b4908             | pop                 ebx
            //   488b4918             | pop                 edi
            //   48f7da               | pop                 esi
            //   486bd218             | ret                 

        $sequence_1 = { 49833e00 498b4608 740a 488b742450 4889c7 eb07 48894308 }
            // n = 7, score = 200
            //   49833e00             | mov                 eax, dword ptr [esp + 0x48]
            //   498b4608             | dec                 eax
            //   740a                 | mov                 dword ptr [esp + 0x160], eax
            //   488b742450           | dec                 ecx
            //   4889c7               | mov                 eax, ebx
            //   eb07                 | dec                 ecx
            //   48894308             | cmp                 ecx, ecx

        $sequence_2 = { b872000000 4189c7 41b405 8d850000efff 81fd00001100 b903000000 0f43c8 }
            // n = 7, score = 200
            //   b872000000           | lea                 ecx, [0x118416]
            //   4189c7               | nop                 word ptr [eax + eax]
            //   41b405               | mov                 eax, 0x27
            //   8d850000efff         | dec                 ecx
            //   81fd00001100         | cmp                 ebx, 0x2710
            //   b903000000           | jb                  0x34f
            //   0f43c8               | mov                 ecx, 0x27

        $sequence_3 = { 7408 4889c1 e8???????? 4885ed 0f95c1 48ff03 eb02 }
            // n = 7, score = 200
            //   7408                 | dec                 esp
            //   4889c1               | cmp                 eax, ebp
            //   e8????????           |                     
            //   4885ed               | je                  0x238
            //   0f95c1               | dec                 eax
            //   48ff03               | lea                 eax, [ecx + 2]
            //   eb02                 | dec                 esp

        $sequence_4 = { a810 0f85d9000000 a820 0f8536010000 4c8b19 b827000000 4981fb10270000 }
            // n = 7, score = 200
            //   a810                 | jne                 0x1a7
            //   0f85d9000000         | dec                 ecx
            //   a820                 | mov                 dword ptr [ecx], 0
            //   0f8536010000         | xor                 edi, edi
            //   4c8b19               | dec                 esp
            //   b827000000           | mov                 ecx, esi
            //   4981fb10270000       | test                al, 1

        $sequence_5 = { 56 57 55 53 4881ece8010000 4889ce 488b3a }
            // n = 7, score = 200
            //   56                   | push                edi
            //   57                   | push                ebx
            //   55                   | dec                 eax
            //   53                   | sub                 esp, 0x28
            //   4881ece8010000       | dec                 ebp
            //   4889ce               | mov                 edi, eax
            //   488b3a               | dec                 ecx

        $sequence_6 = { e8???????? 48837c242000 0f84b6000000 0f10442420 0f104c2430 0f294c2450 0f29442440 }
            // n = 7, score = 200
            //   e8????????           |                     
            //   48837c242000         | movups              xmmword ptr [esi + 2], xmm0
            //   0f84b6000000         | inc                 esp
            //   0f10442420           | mov                 byte ptr [edi], bh
            //   0f104c2430           | inc                 esp
            //   0f294c2450           | mov                 byte ptr [edi + 1], ah
            //   0f29442440           | movaps              xmm0, xmmword ptr [esp + 0x60]

        $sequence_7 = { 89c1 c1e916 83e13f 418a8c0c00010000 41884e0e 4983ff0f 0f8431060000 }
            // n = 7, score = 200
            //   89c1                 | dec                 eax
            //   c1e916               | lea                 edx, [0xddaaa]
            //   83e13f               | dec                 esp
            //   418a8c0c00010000     | lea                 ecx, [0xddad3]
            //   41884e0e             | mov                 ecx, eax
            //   4983ff0f             | dec                 ebp
            //   0f8431060000         | mov                 eax, edi

        $sequence_8 = { e8???????? 4889c3 488d4c2428 488901 e8???????? 4885db 7421 }
            // n = 7, score = 200
            //   e8????????           |                     
            //   4889c3               | dec                 eax
            //   488d4c2428           | mov                 edx, dword ptr [esp + 0x138]
            //   488901               | dec                 eax
            //   e8????????           |                     
            //   4885db               | mov                 dword ptr [esp + 0x370], edx
            //   7421                 | dec                 eax

        $sequence_9 = { 415f c3 4939f0 7309 42803c01c0 7d04 eb13 }
            // n = 7, score = 200
            //   415f                 | imul                eax, eax, 0x18
            //   c3                   | dec                 eax
            //   4939f0               | add                 ecx, eax
            //   7309                 | inc                 ecx
            //   42803c01c0           | pop                 edi
            //   7d04                 | ret                 
            //   eb13                 | dec                 eax

    condition:
        7 of them and filesize < 3532800
}