rule win_goldbackdoor_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.goldbackdoor."
        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.goldbackdoor"
        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 = { 740e 8b6c2448 8bf5 81e6c0000000 eb09 83cfff 33f6 }
            // n = 7, score = 100
            //   740e                 | je                  0x10
            //   8b6c2448             | mov                 ebp, dword ptr [esp + 0x48]
            //   8bf5                 | mov                 esi, ebp
            //   81e6c0000000         | and                 esi, 0xc0
            //   eb09                 | jmp                 0xb
            //   83cfff               | or                  edi, 0xffffffff
            //   33f6                 | xor                 esi, esi

        $sequence_1 = { 8a01 41 84c0 75f9 2bca 51 8d8550faffff }
            // n = 7, score = 100
            //   8a01                 | mov                 al, byte ptr [ecx]
            //   41                   | inc                 ecx
            //   84c0                 | test                al, al
            //   75f9                 | jne                 0xfffffffb
            //   2bca                 | sub                 ecx, edx
            //   51                   | push                ecx
            //   8d8550faffff         | lea                 eax, [ebp - 0x5b0]

        $sequence_2 = { 753c b841000000 68ba000000 68???????? 50 68bd000000 6a0d }
            // n = 7, score = 100
            //   753c                 | jne                 0x3e
            //   b841000000           | mov                 eax, 0x41
            //   68ba000000           | push                0xba
            //   68????????           |                     
            //   50                   | push                eax
            //   68bd000000           | push                0xbd
            //   6a0d                 | push                0xd

        $sequence_3 = { 50 e8???????? 8bf0 8d85c0fbffff 3bc6 7445 8b85d4fbffff }
            // n = 7, score = 100
            //   50                   | push                eax
            //   e8????????           |                     
            //   8bf0                 | mov                 esi, eax
            //   8d85c0fbffff         | lea                 eax, [ebp - 0x440]
            //   3bc6                 | cmp                 eax, esi
            //   7445                 | je                  0x47
            //   8b85d4fbffff         | mov                 eax, dword ptr [ebp - 0x42c]

        $sequence_4 = { 64a300000000 8b7508 6a00 6a00 897580 89b56cffffff c78570ffffff00000000 }
            // n = 7, score = 100
            //   64a300000000         | mov                 dword ptr fs:[0], eax
            //   8b7508               | mov                 esi, dword ptr [ebp + 8]
            //   6a00                 | push                0
            //   6a00                 | push                0
            //   897580               | mov                 dword ptr [ebp - 0x80], esi
            //   89b56cffffff         | mov                 dword ptr [ebp - 0x94], esi
            //   c78570ffffff00000000     | mov    dword ptr [ebp - 0x90], 0

        $sequence_5 = { ffd7 8985d4fbffff 68???????? ffb5fcfbffff ffd7 8985d8fbffff 68???????? }
            // n = 7, score = 100
            //   ffd7                 | call                edi
            //   8985d4fbffff         | mov                 dword ptr [ebp - 0x42c], eax
            //   68????????           |                     
            //   ffb5fcfbffff         | push                dword ptr [ebp - 0x404]
            //   ffd7                 | call                edi
            //   8985d8fbffff         | mov                 dword ptr [ebp - 0x428], eax
            //   68????????           |                     

        $sequence_6 = { 8d542444 f7de 83c410 23c6 8b742418 8bc8 23c3 }
            // n = 7, score = 100
            //   8d542444             | lea                 edx, [esp + 0x44]
            //   f7de                 | neg                 esi
            //   83c410               | add                 esp, 0x10
            //   23c6                 | and                 eax, esi
            //   8b742418             | mov                 esi, dword ptr [esp + 0x18]
            //   8bc8                 | mov                 ecx, eax
            //   23c3                 | and                 eax, ebx

        $sequence_7 = { e8???????? 8b8330020000 83c404 83f803 7755 ff2485b8134200 e8???????? }
            // n = 7, score = 100
            //   e8????????           |                     
            //   8b8330020000         | mov                 eax, dword ptr [ebx + 0x230]
            //   83c404               | add                 esp, 4
            //   83f803               | cmp                 eax, 3
            //   7755                 | ja                  0x57
            //   ff2485b8134200       | jmp                 dword ptr [eax*4 + 0x4213b8]
            //   e8????????           |                     

        $sequence_8 = { ff7740 8b4708 53 ff7710 8b4018 52 55 }
            // n = 7, score = 100
            //   ff7740               | push                dword ptr [edi + 0x40]
            //   8b4708               | mov                 eax, dword ptr [edi + 8]
            //   53                   | push                ebx
            //   ff7710               | push                dword ptr [edi + 0x10]
            //   8b4018               | mov                 eax, dword ptr [eax + 0x18]
            //   52                   | push                edx
            //   55                   | push                ebp

        $sequence_9 = { e8???????? 8d8dacfbffff 0f1000 0f11856cfbffff f30f7e4010 660fd6857cfbffff 8b4018 }
            // n = 7, score = 100
            //   e8????????           |                     
            //   8d8dacfbffff         | lea                 ecx, [ebp - 0x454]
            //   0f1000               | movups              xmm0, xmmword ptr [eax]
            //   0f11856cfbffff       | movups              xmmword ptr [ebp - 0x494], xmm0
            //   f30f7e4010           | movq                xmm0, qword ptr [eax + 0x10]
            //   660fd6857cfbffff     | movq                qword ptr [ebp - 0x484], xmm0
            //   8b4018               | mov                 eax, dword ptr [eax + 0x18]

    condition:
        7 of them and filesize < 2455552
}