rule win_chiser_client_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.chiser_client."
        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.chiser_client"
        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 = { 66896c2464 48896c2430 896c2428 48896c2420 4533c9 4c8d442450 ba00100000 }
            // n = 7, score = 100
            //   66896c2464           | dec                 eax
            //   48896c2430           | add                 esp, 0x20
            //   896c2428             | inc                 ecx
            //   48896c2420           | pop                 edi
            //   4533c9               | dec                 ebx
            //   4c8d442450           | mov                 ecx, dword ptr [edi + esi*8 + 0x4dca0]
            //   ba00100000           | dec                 eax

        $sequence_1 = { 483305???????? 488d15c0df0200 488bcb 488905???????? ff15???????? 483305???????? }
            // n = 6, score = 100
            //   483305????????       |                     
            //   488d15c0df0200       | inc                 esi
            //   488bcb               | movzx               edx, byte ptr [eax + ecx]
            //   488905????????       |                     
            //   ff15????????         |                     
            //   483305????????       |                     

        $sequence_2 = { c7431430000000 488bcb e8???????? 4c8d05e4ca0300 c7431828005700 ba50000000 c7431c69000000 }
            // n = 7, score = 100
            //   c7431430000000       | dec                 eax
            //   488bcb               | lea                 ecx, [esp + 0x20]
            //   e8????????           |                     
            //   4c8d05e4ca0300       | test                eax, eax
            //   c7431828005700       | je                  0x2f0
            //   ba50000000           | and                 dword ptr [esp + 0x30], 0
            //   c7431c69000000       | dec                 eax

        $sequence_3 = { 48875308 4c396b08 7521 8364242800 488d057ba5ffff 4889442430 }
            // n = 6, score = 100
            //   48875308             | inc                 ecx
            //   4c396b08             | mov                 bh, al
            //   7521                 | dec                 eax
            //   8364242800           | mov                 ebx, ecx
            //   488d057ba5ffff       | inc                 ecx
            //   4889442430           | mov                 al, 1

        $sequence_4 = { ff15???????? 483305???????? 488d1570df0200 488bcb 488905???????? ff15???????? 483305???????? }
            // n = 7, score = 100
            //   ff15????????         |                     
            //   483305????????       |                     
            //   488d1570df0200       | sub                 eax, edx
            //   488bcb               | dec                 eax
            //   488905????????       |                     
            //   ff15????????         |                     
            //   483305????????       |                     

        $sequence_5 = { 4c8d05bcad0200 488d15fda70200 e8???????? 488bd8 4885c0 740f }
            // n = 6, score = 100
            //   4c8d05bcad0200       | dec                 eax
            //   488d15fda70200       | lea                 edx, [0x2a7ba]
            //   e8????????           |                     
            //   488bd8               | dec                 eax
            //   4885c0               | mov                 edi, eax
            //   740f                 | dec                 eax

        $sequence_6 = { 488955c7 33c0 0f57c0 f30f7f45d7 488945e7 48b863003a005c000000 48894507 }
            // n = 7, score = 100
            //   488955c7             | mov                 ebx, dword ptr [esp + 0x30]
            //   33c0                 | dec                 eax
            //   0f57c0               | add                 esp, 0x20
            //   f30f7f45d7           | pop                 edi
            //   488945e7             | ret                 
            //   48b863003a005c000000     | dec    eax
            //   48894507             | lea                 ecx, [0x3df91]

        $sequence_7 = { 4883f80f 765e 488b09 4c8d442420 }
            // n = 4, score = 100
            //   4883f80f             | cmovo               eax, edx
            //   765e                 | dec                 eax
            //   488b09               | mov                 ecx, eax
            //   4c8d442420           | dec                 ecx

        $sequence_8 = { eb05 be01000000 488b0f 4c8d4110 488d5108 e8???????? }
            // n = 6, score = 100
            //   eb05                 | dec                 eax
            //   be01000000           | mov                 dword ptr [esp + 0x30], eax
            //   488b0f               | mov                 dword ptr [esp + 0x28], eax
            //   4c8d4110             | dec                 eax
            //   488d5108             | mov                 dword ptr [esp + 0x20], eax
            //   e8????????           |                     

        $sequence_9 = { 488b5c2430 4883c420 5f c3 488d0d9add0300 e8???????? cc }
            // n = 7, score = 100
            //   488b5c2430           | dec                 eax
            //   4883c420             | mov                 dword ptr [ecx + 0x10], eax
            //   5f                   | dec                 eax
            //   c3                   | lea                 eax, [0x1c7ff]
            //   488d0d9add0300       | dec                 eax
            //   e8????????           |                     
            //   cc                   | mov                 dword ptr [ecx], eax

    condition:
        7 of them and filesize < 714752
}