rule win_poscardstealer_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.poscardstealer."
        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.poscardstealer"
        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 = { 33c0 668b4d08 663b88600a4200 740d 83c002 }
            // n = 5, score = 200
            //   33c0                 | xor                 eax, eax
            //   668b4d08             | mov                 cx, word ptr [ebp + 8]
            //   663b88600a4200       | cmp                 cx, word ptr [eax + 0x420a60]
            //   740d                 | je                  0xf
            //   83c002               | add                 eax, 2

        $sequence_1 = { 64a300000000 8b35???????? 8975ac 3b35???????? 0f84fc000000 }
            // n = 5, score = 200
            //   64a300000000         | mov                 dword ptr fs:[0], eax
            //   8b35????????         |                     
            //   8975ac               | mov                 dword ptr [ebp - 0x54], esi
            //   3b35????????         |                     
            //   0f84fc000000         | je                  0x102

        $sequence_2 = { 8917 83c704 89bd80edffff eb68 8b8d84edffff 3bd1 }
            // n = 6, score = 200
            //   8917                 | mov                 dword ptr [edi], edx
            //   83c704               | add                 edi, 4
            //   89bd80edffff         | mov                 dword ptr [ebp - 0x1280], edi
            //   eb68                 | jmp                 0x6a
            //   8b8d84edffff         | mov                 ecx, dword ptr [ebp - 0x127c]
            //   3bd1                 | cmp                 edx, ecx

        $sequence_3 = { 8b45b0 56 50 51 ff15???????? 8b5590 8bcf }
            // n = 7, score = 200
            //   8b45b0               | mov                 eax, dword ptr [ebp - 0x50]
            //   56                   | push                esi
            //   50                   | push                eax
            //   51                   | push                ecx
            //   ff15????????         |                     
            //   8b5590               | mov                 edx, dword ptr [ebp - 0x70]
            //   8bcf                 | mov                 ecx, edi

        $sequence_4 = { 83ff0c 7e79 8bc7 f7d8 8945c8 eb03 8b45c8 }
            // n = 7, score = 200
            //   83ff0c               | cmp                 edi, 0xc
            //   7e79                 | jle                 0x7b
            //   8bc7                 | mov                 eax, edi
            //   f7d8                 | neg                 eax
            //   8945c8               | mov                 dword ptr [ebp - 0x38], eax
            //   eb03                 | jmp                 5
            //   8b45c8               | mov                 eax, dword ptr [ebp - 0x38]

        $sequence_5 = { 50 8d45f4 64a300000000 8b7508 8b4528 }
            // n = 5, score = 200
            //   50                   | push                eax
            //   8d45f4               | lea                 eax, [ebp - 0xc]
            //   64a300000000         | mov                 dword ptr fs:[0], eax
            //   8b7508               | mov                 esi, dword ptr [ebp + 8]
            //   8b4528               | mov                 eax, dword ptr [ebp + 0x28]

        $sequence_6 = { 8bce c645fc12 e8???????? 837de810 c645fc01 }
            // n = 5, score = 200
            //   8bce                 | mov                 ecx, esi
            //   c645fc12             | mov                 byte ptr [ebp - 4], 0x12
            //   e8????????           |                     
            //   837de810             | cmp                 dword ptr [ebp - 0x18], 0x10
            //   c645fc01             | mov                 byte ptr [ebp - 4], 1

        $sequence_7 = { 68???????? 50 e8???????? 83c40c 3bc7 7514 83fe01 }
            // n = 7, score = 200
            //   68????????           |                     
            //   50                   | push                eax
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc
            //   3bc7                 | cmp                 eax, edi
            //   7514                 | jne                 0x16
            //   83fe01               | cmp                 esi, 1

        $sequence_8 = { 8d34c5f05b4200 833e00 7513 50 e8???????? 59 85c0 }
            // n = 7, score = 200
            //   8d34c5f05b4200       | lea                 esi, [eax*8 + 0x425bf0]
            //   833e00               | cmp                 dword ptr [esi], 0
            //   7513                 | jne                 0x15
            //   50                   | push                eax
            //   e8????????           |                     
            //   59                   | pop                 ecx
            //   85c0                 | test                eax, eax

        $sequence_9 = { 8b45e0 8a8064614200 08443b1d 0fb64601 }
            // n = 4, score = 200
            //   8b45e0               | mov                 eax, dword ptr [ebp - 0x20]
            //   8a8064614200         | mov                 al, byte ptr [eax + 0x426164]
            //   08443b1d             | or                  byte ptr [ebx + edi + 0x1d], al
            //   0fb64601             | movzx               eax, byte ptr [esi + 1]

    condition:
        7 of them and filesize < 362496
}