rule win_darkshell_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.darkshell."
        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.darkshell"
        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 = { ff15???????? 8b33 8b17 8d4c2424 }
            // n = 4, score = 300
            //   ff15????????         |                     
            //   8b33                 | mov                 esi, dword ptr [ebx]
            //   8b17                 | mov                 edx, dword ptr [edi]
            //   8d4c2424             | lea                 ecx, [esp + 0x24]

        $sequence_1 = { 8b4e54 50 51 8bcf e8???????? 66837e0600 }
            // n = 6, score = 300
            //   8b4e54               | mov                 ecx, dword ptr [esi + 0x54]
            //   50                   | push                eax
            //   51                   | push                ecx
            //   8bcf                 | mov                 ecx, edi
            //   e8????????           |                     
            //   66837e0600           | cmp                 word ptr [esi + 6], 0

        $sequence_2 = { 8b0f 8b5138 52 50 }
            // n = 4, score = 300
            //   8b0f                 | mov                 ecx, dword ptr [edi]
            //   8b5138               | mov                 edx, dword ptr [ecx + 0x38]
            //   52                   | push                edx
            //   50                   | push                eax

        $sequence_3 = { 8d7e08 f7c2feffffff 767a 668b07 8bc8 81e100f00000 6681f90030 }
            // n = 7, score = 300
            //   8d7e08               | lea                 edi, [esi + 8]
            //   f7c2feffffff         | test                edx, 0xfffffffe
            //   767a                 | jbe                 0x7c
            //   668b07               | mov                 ax, word ptr [edi]
            //   8bc8                 | mov                 ecx, eax
            //   81e100f00000         | and                 ecx, 0xf000
            //   6681f90030           | cmp                 cx, 0x3000

        $sequence_4 = { 52 8bce 83cfff e8???????? 85c0 7446 }
            // n = 6, score = 300
            //   52                   | push                edx
            //   8bce                 | mov                 ecx, esi
            //   83cfff               | or                  edi, 0xffffffff
            //   e8????????           |                     
            //   85c0                 | test                eax, eax
            //   7446                 | je                  0x48

        $sequence_5 = { 742b 8b55f8 85d2 7412 }
            // n = 4, score = 300
            //   742b                 | je                  0x2d
            //   8b55f8               | mov                 edx, dword ptr [ebp - 8]
            //   85d2                 | test                edx, edx
            //   7412                 | je                  0x14

        $sequence_6 = { 8b4df8 3bc8 7307 8b4e38 51 }
            // n = 5, score = 300
            //   8b4df8               | mov                 ecx, dword ptr [ebp - 8]
            //   3bc8                 | cmp                 ecx, eax
            //   7307                 | jae                 9
            //   8b4e38               | mov                 ecx, dword ptr [esi + 0x38]
            //   51                   | push                ecx

        $sequence_7 = { ff15???????? 8b542410 8d4c2414 51 6a04 52 }
            // n = 6, score = 300
            //   ff15????????         |                     
            //   8b542410             | mov                 edx, dword ptr [esp + 0x10]
            //   8d4c2414             | lea                 ecx, [esp + 0x14]
            //   51                   | push                ecx
            //   6a04                 | push                4
            //   52                   | push                edx

        $sequence_8 = { 83ec1c 8d442400 c744240000000000 50 6a28 ff15???????? }
            // n = 6, score = 300
            //   83ec1c               | sub                 esp, 0x1c
            //   8d442400             | lea                 eax, [esp]
            //   c744240000000000     | mov                 dword ptr [esp], 0
            //   50                   | push                eax
            //   6a28                 | push                0x28
            //   ff15????????         |                     

        $sequence_9 = { 5d 83c474 c21c00 8bc5 5f 5d }
            // n = 6, score = 300
            //   5d                   | pop                 ebp
            //   83c474               | add                 esp, 0x74
            //   c21c00               | ret                 0x1c
            //   8bc5                 | mov                 eax, ebp
            //   5f                   | pop                 edi
            //   5d                   | pop                 ebp

    condition:
        7 of them and filesize < 344064
}