rule win_santa_stealer_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.santa_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.santa_stealer"
        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 = { 4c29e8 0fb6fc 4863d0 4989ff 89c7 4139c1 0f8ca5f8ffff }
            // n = 7, score = 100
            //   4c29e8               | imul                eax, eax, 0x88888889
            //   0fb6fc               | cvtsi2sd            xmm0, ecx
            //   4863d0               | dec                 eax
            //   4989ff               | shr                 eax, 0x20
            //   89c7                 | inc                 ecx
            //   4139c1               | sar                 eax, 0x1f
            //   0f8ca5f8ffff         | dec                 eax

        $sequence_1 = { e8???????? 488b0f 4885c9 75f3 8b4320 394328 0f82d6000000 }
            // n = 7, score = 100
            //   e8????????           |                     
            //   488b0f               | movups              xmmword ptr [esp + 0x28], xmm0
            //   4885c9               | dec                 eax
            //   75f3                 | lea                 esi, [esp + 0x30]
            //   8b4320               | inc                 ecx
            //   394328               | cmp                 eax, 1
            //   0f82d6000000         | jle                 0x10a9

        $sequence_2 = { e9???????? 8b5328 85d2 7ebc 488b4320 4863ca 48c1e105 }
            // n = 7, score = 100
            //   e9????????           |                     
            //   8b5328               | test                eax, eax
            //   85d2                 | jne                 0x915
            //   7ebc                 | dec                 ecx
            //   488b4320             | add                 esi, 1
            //   4863ca               | inc                 esp
            //   48c1e105             | cmp                 eax, esi

        $sequence_3 = { c3 8d4601 668903 0fb7c6 48c1e604 66897c3312 48c1e004 }
            // n = 7, score = 100
            //   c3                   | push                ebp
            //   8d4601               | inc                 ecx
            //   668903               | push                esp
            //   0fb7c6               | dec                 eax
            //   48c1e604             | lea                 eax, [0x977388]
            //   66897c3312           | cmp                 byte ptr [ecx + 0x67], 0
            //   48c1e004             | jne                 0x1546

        $sequence_4 = { 803806 772e 4c8b4748 4d85c0 7417 488d15c79bf8ff 4889f1 }
            // n = 7, score = 100
            //   803806               | dec                 esp
            //   772e                 | mov                 esi, dword ptr [eax + 0x10]
            //   4c8b4748             | dec                 eax
            //   4d85c0               | mov                 dword ptr [esp + 0xa8], eax
            //   7417                 | dec                 eax
            //   488d15c79bf8ff       | mov                 eax, dword ptr [eax]
            //   4889f1               | dec                 eax

        $sequence_5 = { e8???????? 8b8424cc000000 85c0 0f85720b0000 488b8424b8000000 458b4730 4889f1 }
            // n = 7, score = 100
            //   e8????????           |                     
            //   8b8424cc000000       | je                  0x1c31
            //   85c0                 | inc                 ebp
            //   0f85720b0000         | test                esp, esp
            //   488b8424b8000000     | jne                 0x1c31
            //   458b4730             | inc                 sp
            //   4889f1               | mov                 dword ptr [edi + 6], ebp

        $sequence_6 = { e8???????? 4885c0 7434 488b4d10 660fefc0 48639124020000 48c744d02000000000 }
            // n = 7, score = 100
            //   e8????????           |                     
            //   4885c0               | inc                 esp
            //   7434                 | mov                 ecx, edx
            //   488b4d10             | inc                 ecx
            //   660fefc0             | cmp                 edx, eax
            //   48639124020000       | jb                  0x1d81
            //   48c744d02000000000     | dec    esp

        $sequence_7 = { e8???????? 4885c0 0f843a040000 41c78424900d000001000000 4889f1 e8???????? 4981c700020000 }
            // n = 7, score = 100
            //   e8????????           |                     
            //   4885c0               | dec                 eax
            //   0f843a040000         | lea                 ecx, [esp + 0x70]
            //   41c78424900d000001000000     | test    eax, eax
            //   4889f1               | jne                 0x11b9
            //   e8????????           |                     
            //   4981c700020000       | dec                 esp

        $sequence_8 = { c744242804000000 4531c9 31d2 4889d9 48c744242000000000 4c8d842490000000 e8???????? }
            // n = 7, score = 100
            //   c744242804000000     | dec                 eax
            //   4531c9               | mov                 dword ptr [esp + 0x20], eax
            //   31d2                 | test                eax, eax
            //   4889d9               | jne                 0x248
            //   48c744242000000000     | dec    eax
            //   4c8d842490000000     | lea                 eax, [esp + 0x34]
            //   e8????????           |                     

        $sequence_9 = { f6401260 74d7 0fb74010 6685c0 0f84c2080000 807e3f00 0f85b8080000 }
            // n = 7, score = 100
            //   f6401260             | mov                 ecx, dword ptr [ecx]
            //   74d7                 | xor                 eax, eax
            //   0fb74010             | dec                 esp
            //   6685c0               | mov                 edx, dword ptr [ecx + 0x80]
            //   0f84c2080000         | dec                 ebp
            //   807e3f00             | test                edx, edx
            //   0f85b8080000         | je                  0xf70

    condition:
        7 of them and filesize < 27009024
}