rule win_gooseegg_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.gooseegg."
        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.gooseegg"
        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 = { eb2e 41b901000000 c645cc01 4c8d45cc c74424200d000000 }
            // n = 5, score = 100
            //   eb2e                 | xchg                dword ptr [esi + esi*8 + 0x17318], eax
            //   41b901000000         | dec                 eax
            //   c645cc01             | test                eax, eax
            //   4c8d45cc             | je                  0x344
            //   c74424200d000000     | dec                 eax

        $sequence_1 = { 488bda 4c8d0d60b10000 8bf9 488d1557b10000 b903000000 4c8d0543b10000 }
            // n = 6, score = 100
            //   488bda               | mov                 eax, eax
            //   4c8d0d60b10000       | mov                 dl, 1
            //   8bf9                 | mov                 ecx, 0xfffffffd
            //   488d1557b10000       | dec                 esp
            //   b903000000           | lea                 ecx, [0x7ce8]
            //   4c8d0543b10000       | mov                 ecx, 0x1c

        $sequence_2 = { 85c0 7568 4889742430 8d5002 c744242800010004 448d4007 }
            // n = 6, score = 100
            //   85c0                 | dec                 eax
            //   7568                 | cmp                 ecx, eax
            //   4889742430           | je                  0x4e2
            //   8d5002               | mov                 eax, dword ptr [ecx + 0x15c]
            //   c744242800010004     | dec                 eax
            //   448d4007             | sub                 esp, 0x20

        $sequence_3 = { 498784f670770100 eb1e 488bc3 498784f670770100 4885c0 7409 }
            // n = 6, score = 100
            //   498784f670770100     | dec                 edx
            //   eb1e                 | movsx               edi, byte ptr [eax + edi + 0x168c0]
            //   488bc3               | lea                 ecx, [edi + 1]
            //   498784f670770100     | dec                 eax
            //   4885c0               | arpl                cx, ax
            //   7409                 | movzx               eax, ax

        $sequence_4 = { 488d05a6490100 483bd8 7408 488bcb e8???????? 4883c420 }
            // n = 6, score = 100
            //   488d05a6490100       | lea                 edx, [esi + 4]
            //   483bd8               | dec                 eax
            //   7408                 | lea                 ecx, [esi - 2]
            //   488bcb               | inc                 esp
            //   e8????????           |                     
            //   4883c420             | lea                 eax, [esi + 1]

        $sequence_5 = { 4c8d0d95b10000 b902000000 4c8d0581b10000 488d1582b10000 e8???????? 8bcb }
            // n = 6, score = 100
            //   4c8d0d95b10000       | push                edi
            //   b902000000           | dec                 eax
            //   4c8d0581b10000       | sub                 esp, 0x20
            //   488d1582b10000       | inc                 esp
            //   e8????????           |                     
            //   8bcb                 | mov                 edi, ecx

        $sequence_6 = { e9???????? 8a06 4c8d057163ffff 4b8b8ce030790100 ffc3 }
            // n = 5, score = 100
            //   e9????????           |                     
            //   8a06                 | dec                 eax
            //   4c8d057163ffff       | mov                 esi, dword ptr [esp + 0x980]
            //   4b8b8ce030790100     | dec                 eax
            //   ffc3                 | add                 esp, 0x960

        $sequence_7 = { 4c8d2dc6fd0000 448bf3 498bc5 8d6b01 3938 0f844e010000 4403f5 }
            // n = 7, score = 100
            //   4c8d2dc6fd0000       | test                cl, 4
            //   448bf3               | je                  0x60c
            //   498bc5               | inc                 esp
            //   8d6b01               | lea                 eax, [eax + 7]
            //   3938                 | inc                 ebp
            //   0f844e010000         | xor                 ecx, ecx
            //   4403f5               | mov                 dword ptr [esp + 0x20], 1

        $sequence_8 = { 83c8ff f00fc101 83f801 751f 488b0d???????? 488d1dc9210100 483bcb }
            // n = 7, score = 100
            //   83c8ff               | sub                 esp, 0x28
            //   f00fc101             | dec                 eax
            //   83f801               | test                eax, eax
            //   751f                 | jne                 0x428
            //   488b0d????????       |                     
            //   488d1dc9210100       | dec                 eax
            //   483bcb               | lea                 eax, [0x1184f]

        $sequence_9 = { 498bf8 8bf2 4c8d0d897a0000 488be9 4c8d05777a0000 488d15787a0000 }
            // n = 6, score = 100
            //   498bf8               | dec                 eax
            //   8bf2                 | mov                 dword ptr [ecx + 8], eax
            //   4c8d0d897a0000       | dec                 eax
            //   488be9               | mov                 dword ptr [ecx + 0x10], eax
            //   4c8d05777a0000       | mov                 dword ptr [ecx + 0x18], eax
            //   488d15787a0000       | dec                 eax

    condition:
        7 of them and filesize < 217088
}