rule win_chewbacca_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.chewbacca."
        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.chewbacca"
        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 = { e8???????? eb55 8b442478 89442414 895c2410 c744240c9c976600 c7442408???????? }
            // n = 7, score = 100
            //   e8????????           |                     
            //   eb55                 | jmp                 0x57
            //   8b442478             | mov                 eax, dword ptr [esp + 0x78]
            //   89442414             | mov                 dword ptr [esp + 0x14], eax
            //   895c2410             | mov                 dword ptr [esp + 0x10], ebx
            //   c744240c9c976600     | mov                 dword ptr [esp + 0xc], 0x66979c
            //   c7442408????????     |                     

        $sequence_1 = { ff33 74fd 0389cfc1ef10 81e7ff000000 3374fd02 89d7 c1ef18 }
            // n = 7, score = 100
            //   ff33                 | push                dword ptr [ebx]
            //   74fd                 | je                  0xffffffff
            //   0389cfc1ef10         | add                 ecx, dword ptr [ecx + 0x10efc1cf]
            //   81e7ff000000         | and                 edi, 0xff
            //   3374fd02             | xor                 esi, dword ptr [ebp + edi*8 + 2]
            //   89d7                 | mov                 edi, edx
            //   c1ef18               | shr                 edi, 0x18

        $sequence_2 = { e8???????? c744241426a36700 c744241048cf6700 c744240c20060000 89442408 c7442404???????? a1???????? }
            // n = 7, score = 100
            //   e8????????           |                     
            //   c744241426a36700     | mov                 dword ptr [esp + 0x14], 0x67a326
            //   c744241048cf6700     | mov                 dword ptr [esp + 0x10], 0x67cf48
            //   c744240c20060000     | mov                 dword ptr [esp + 0xc], 0x620
            //   89442408             | mov                 dword ptr [esp + 8], eax
            //   c7442404????????     |                     
            //   a1????????           |                     

        $sequence_3 = { a3???????? 8b442424 89442408 8b442420 89442404 a1???????? 890424 }
            // n = 7, score = 100
            //   a3????????           |                     
            //   8b442424             | mov                 eax, dword ptr [esp + 0x24]
            //   89442408             | mov                 dword ptr [esp + 8], eax
            //   8b442420             | mov                 eax, dword ptr [esp + 0x20]
            //   89442404             | mov                 dword ptr [esp + 4], eax
            //   a1????????           |                     
            //   890424               | mov                 dword ptr [esp], eax

        $sequence_4 = { c7042424040000 e8???????? 89c2 85c0 0f84a0000000 89c7 be24040000 }
            // n = 7, score = 100
            //   c7042424040000       | mov                 dword ptr [esp], 0x424
            //   e8????????           |                     
            //   89c2                 | mov                 edx, eax
            //   85c0                 | test                eax, eax
            //   0f84a0000000         | je                  0xa6
            //   89c7                 | mov                 edi, eax
            //   be24040000           | mov                 esi, 0x424

        $sequence_5 = { e8???????? c7042401000000 e8???????? e8???????? 89c3 e8???????? 895c2410 }
            // n = 7, score = 100
            //   e8????????           |                     
            //   c7042401000000       | mov                 dword ptr [esp], 1
            //   e8????????           |                     
            //   e8????????           |                     
            //   89c3                 | mov                 ebx, eax
            //   e8????????           |                     
            //   895c2410             | mov                 dword ptr [esp + 0x10], ebx

        $sequence_6 = { eb0c be00000000 eb05 be00000000 89f0 83c410 5b }
            // n = 7, score = 100
            //   eb0c                 | jmp                 0xe
            //   be00000000           | mov                 esi, 0
            //   eb05                 | jmp                 7
            //   be00000000           | mov                 esi, 0
            //   89f0                 | mov                 eax, esi
            //   83c410               | add                 esp, 0x10
            //   5b                   | pop                 ebx

        $sequence_7 = { f2ae f7d1 8b442440 8d4408ff 89442440 e9???????? 89e8 }
            // n = 7, score = 100
            //   f2ae                 | repne scasb         al, byte ptr es:[edi]
            //   f7d1                 | not                 ecx
            //   8b442440             | mov                 eax, dword ptr [esp + 0x40]
            //   8d4408ff             | lea                 eax, [eax + ecx - 1]
            //   89442440             | mov                 dword ptr [esp + 0x40], eax
            //   e9????????           |                     
            //   89e8                 | mov                 eax, ebp

        $sequence_8 = { 8945fc 89d3 89ce 8a4508 84c0 7409 8b45fc }
            // n = 7, score = 100
            //   8945fc               | mov                 dword ptr [ebp - 4], eax
            //   89d3                 | mov                 ebx, edx
            //   89ce                 | mov                 esi, ecx
            //   8a4508               | mov                 al, byte ptr [ebp + 8]
            //   84c0                 | test                al, al
            //   7409                 | je                  0xb
            //   8b45fc               | mov                 eax, dword ptr [ebp - 4]

        $sequence_9 = { 8b542454 8b442450 e8???????? 85c0 740b 83c43c 5b }
            // n = 7, score = 100
            //   8b542454             | mov                 edx, dword ptr [esp + 0x54]
            //   8b442450             | mov                 eax, dword ptr [esp + 0x50]
            //   e8????????           |                     
            //   85c0                 | test                eax, eax
            //   740b                 | je                  0xd
            //   83c43c               | add                 esp, 0x3c
            //   5b                   | pop                 ebx

    condition:
        7 of them and filesize < 9764864
}