rule win_valkyrie_stealer_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.valkyrie_stealer."
        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.valkyrie_stealer"
        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 = { c744242074cd0000 8bd0 4c8d0561e70300 b90e030000 e8???????? eb22 83c503 }
            // n = 7, score = 100
            //   c744242074cd0000     | dec                 eax
            //   8bd0                 | mov                 esi, dword ptr [esp + 0x60]
            //   4c8d0561e70300       | dec                 eax
            //   b90e030000           | mov                 edx, esi
            //   e8????????           |                     
            //   eb22                 | dec                 esp
            //   83c503               | sub                 ecx, ebp

        $sequence_1 = { c704c80e000000 448944c804 448944c80c 488d14c8 8b842480000000 48897a10 894208 }
            // n = 7, score = 100
            //   c704c80e000000       | dec                 eax
            //   448944c804           | mov                 ecx, edi
            //   448944c80c           | test                eax, eax
            //   488d14c8             | je                  0x31b
            //   8b842480000000       | inc                 esp
            //   48897a10             | mov                 eax, dword ptr [ebp + 0x77]
            //   894208               | inc                 ebp

        $sequence_2 = { 7f1f 41b903000000 44896c2420 4533c0 ba76000000 488bcb e8???????? }
            // n = 7, score = 100
            //   7f1f                 | dec                 eax
            //   41b903000000         | mov                 ecx, ebp
            //   44896c2420           | test                eax, eax
            //   4533c0               | jne                 0x408
            //   ba76000000           | dec                 ebx
            //   488bcb               | dec                 eax
            //   e8????????           |                     

        $sequence_3 = { 80f980 7513 83e03f c1e206 03d0 41ffc1 49ffc0 }
            // n = 7, score = 100
            //   80f980               | cmp                 dword ptr [ebp + 0x6f], 0
            //   7513                 | dec                 eax
            //   83e03f               | test                edi, edi
            //   c1e206               | je                  0xe2c
            //   03d0                 | dec                 eax
            //   41ffc1               | mov                 edx, edi
            //   49ffc0               | dec                 ecx

        $sequence_4 = { ba5e000000 488bcb e8???????? 4533d2 eb2d 8d4101 898390000000 }
            // n = 7, score = 100
            //   ba5e000000           | dec                 ecx
            //   488bcb               | mov                 edx, edi
            //   e8????????           |                     
            //   4533d2               | dec                 eax
            //   eb2d                 | mov                 ecx, eax
            //   8d4101               | dec                 eax
            //   898390000000         | lea                 edx, [ebp - 0x60]

        $sequence_5 = { 488d0c49 488b8388000000 c704c85e000000 44897cc804 897cc808 448954c80c 4c896cc810 }
            // n = 7, score = 100
            //   488d0c49             | dec                 ecx
            //   488b8388000000       | inc                 ecx
            //   c704c85e000000       | dec                 ecx
            //   44897cc804           | inc                 edx
            //   897cc808             | inc                 ebp
            //   448954c80c           | test                eax, eax
            //   4c896cc810           | jg                  0x1b46

        $sequence_6 = { 85c6 7577 8d86fffeffff 3dfffe0000 776a 0fb64714 448be6 }
            // n = 7, score = 100
            //   85c6                 | dec                 ecx
            //   7577                 | mov                 edx, esi
            //   8d86fffeffff         | dec                 eax
            //   3dfffe0000           | mov                 dword ptr [ebp - 0x60], edi
            //   776a                 | dec                 ecx
            //   0fb64714             | mov                 ecx, edi
            //   448be6               | dec                 eax

        $sequence_7 = { 8954c80c 4c895cc810 83bc24e001000000 488b842490000000 7442 493bc7 753d }
            // n = 7, score = 100
            //   8954c80c             | je                  0x45b
            //   4c895cc810           | dec                 eax
            //   83bc24e001000000     | mov                 eax, dword ptr [eax + 8]
            //   488b842490000000     | dec                 ecx
            //   7442                 | mov                 ecx, esi
            //   493bc7               | movzx               ebx, byte ptr [edi + 0x10]
            //   753d                 | call                eax

        $sequence_8 = { 7418 488d1533081000 488bcb e8???????? 48894558 be01000000 488b4f08 }
            // n = 7, score = 100
            //   7418                 | inc                 ebp
            //   488d1533081000       | mov                 dword ptr [eax + 0x3c], esp
            //   488bcb               | inc                 ecx
            //   e8????????           |                     
            //   48894558             | movzx               eax, byte ptr [ebp + 0x21]
            //   be01000000           | inc                 esp
            //   488b4f08             | mov                 dword ptr [ebp - 0x39], esp

        $sequence_9 = { 7419 0fbae20e 7307 483b6c2478 740c 4d8bc3 488d15ea260c00 }
            // n = 7, score = 100
            //   7419                 | arpl                ax, di
            //   0fbae20e             | inc                 ebp
            //   7307                 | mov                 dword ptr [ebx - 0x14], esi
            //   483b6c2478           | cmp                 ebp, 1
            //   740c                 | jne                 0x1d9f
            //   4d8bc3               | dec                 eax
            //   488d15ea260c00       | mov                 ecx, edi

    condition:
        7 of them and filesize < 2895872
}