rule win_furtim_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.furtim."
        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.furtim"
        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 = { 8bf8 0bc2 74eb 8bcf ff96b8020000 53 53 }
            // n = 7, score = 100
            //   8bf8                 | mov                 edi, eax
            //   0bc2                 | or                  eax, edx
            //   74eb                 | je                  0xffffffed
            //   8bcf                 | mov                 ecx, edi
            //   ff96b8020000         | call                dword ptr [esi + 0x2b8]
            //   53                   | push                ebx
            //   53                   | push                ebx

        $sequence_1 = { 8d8628030000 8945b8 8d4638 8945bc 8945c8 8d86ec060000 8945cc }
            // n = 7, score = 100
            //   8d8628030000         | lea                 eax, [esi + 0x328]
            //   8945b8               | mov                 dword ptr [ebp - 0x48], eax
            //   8d4638               | lea                 eax, [esi + 0x38]
            //   8945bc               | mov                 dword ptr [ebp - 0x44], eax
            //   8945c8               | mov                 dword ptr [ebp - 0x38], eax
            //   8d86ec060000         | lea                 eax, [esi + 0x6ec]
            //   8945cc               | mov                 dword ptr [ebp - 0x34], eax

        $sequence_2 = { 39a9c0000000 7542 0fb781cc010000 663bc5 7405 663bc3 }
            // n = 6, score = 100
            //   39a9c0000000         | cmp                 dword ptr [ecx + 0xc0], ebp
            //   7542                 | jne                 0x44
            //   0fb781cc010000       | movzx               eax, word ptr [ecx + 0x1cc]
            //   663bc5               | cmp                 ax, bp
            //   7405                 | je                  7
            //   663bc3               | cmp                 ax, bx

        $sequence_3 = { 8bd7 8bce ff9628060000 8bce 84c0 75ea }
            // n = 6, score = 100
            //   8bd7                 | mov                 edx, edi
            //   8bce                 | mov                 ecx, esi
            //   ff9628060000         | call                dword ptr [esi + 0x628]
            //   8bce                 | mov                 ecx, esi
            //   84c0                 | test                al, al
            //   75ea                 | jne                 0xffffffec

        $sequence_4 = { 5b c3 56 8bf1 57 b9feff0000 ff96b8020000 }
            // n = 7, score = 100
            //   5b                   | pop                 ebx
            //   c3                   | ret                 
            //   56                   | push                esi
            //   8bf1                 | mov                 esi, ecx
            //   57                   | push                edi
            //   b9feff0000           | mov                 ecx, 0xfffe
            //   ff96b8020000         | call                dword ptr [esi + 0x2b8]

        $sequence_5 = { ff90c8040000 59 59 85c0 7541 8b45f8 }
            // n = 6, score = 100
            //   ff90c8040000         | call                dword ptr [eax + 0x4c8]
            //   59                   | pop                 ecx
            //   59                   | pop                 ecx
            //   85c0                 | test                eax, eax
            //   7541                 | jne                 0x43
            //   8b45f8               | mov                 eax, dword ptr [ebp - 8]

        $sequence_6 = { 3999c0000000 7540 663999cc010000 7537 663999ce010000 752e 81b9c400000000280000 }
            // n = 7, score = 100
            //   3999c0000000         | cmp                 dword ptr [ecx + 0xc0], ebx
            //   7540                 | jne                 0x42
            //   663999cc010000       | cmp                 word ptr [ecx + 0x1cc], bx
            //   7537                 | jne                 0x39
            //   663999ce010000       | cmp                 word ptr [ecx + 0x1ce], bx
            //   752e                 | jne                 0x30
            //   81b9c400000000280000     | cmp    dword ptr [ecx + 0xc4], 0x2800

        $sequence_7 = { 84c0 75db 8b45f8 8b4df8 83caff ff90fc020000 ebca }
            // n = 7, score = 100
            //   84c0                 | test                al, al
            //   75db                 | jne                 0xffffffdd
            //   8b45f8               | mov                 eax, dword ptr [ebp - 8]
            //   8b4df8               | mov                 ecx, dword ptr [ebp - 8]
            //   83caff               | or                  edx, 0xffffffff
            //   ff90fc020000         | call                dword ptr [eax + 0x2fc]
            //   ebca                 | jmp                 0xffffffcc

        $sequence_8 = { 8b45f8 3998b0050000 0f85f4000000 8b45f8 }
            // n = 4, score = 100
            //   8b45f8               | mov                 eax, dword ptr [ebp - 8]
            //   3998b0050000         | cmp                 dword ptr [eax + 0x5b0], ebx
            //   0f85f4000000         | jne                 0xfa
            //   8b45f8               | mov                 eax, dword ptr [ebp - 8]

        $sequence_9 = { 83ec68 53 56 68???????? 8bf1 }
            // n = 5, score = 100
            //   83ec68               | sub                 esp, 0x68
            //   53                   | push                ebx
            //   56                   | push                esi
            //   68????????           |                     
            //   8bf1                 | mov                 esi, ecx

    condition:
        7 of them and filesize < 622592
}