rule win_exaramel_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.exaramel."
        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.exaramel"
        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 = { 660fd60f 8d7f08 8b048d74404100 ffe0 f7c703000000 7413 8a06 }
            // n = 7, score = 100
            //   660fd60f             | movq                qword ptr [edi], xmm1
            //   8d7f08               | lea                 edi, [edi + 8]
            //   8b048d74404100       | mov                 eax, dword ptr [ecx*4 + 0x414074]
            //   ffe0                 | jmp                 eax
            //   f7c703000000         | test                edi, 3
            //   7413                 | je                  0x15
            //   8a06                 | mov                 al, byte ptr [esi]

        $sequence_1 = { e8???????? 8bc7 83c404 8b4dfc 5f 33cd }
            // n = 6, score = 100
            //   e8????????           |                     
            //   8bc7                 | mov                 eax, edi
            //   83c404               | add                 esp, 4
            //   8b4dfc               | mov                 ecx, dword ptr [ebp - 4]
            //   5f                   | pop                 edi
            //   33cd                 | xor                 ecx, ebp

        $sequence_2 = { ff15???????? 85c0 746d 53 57 ff75fc 8b3d???????? }
            // n = 7, score = 100
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax
            //   746d                 | je                  0x6f
            //   53                   | push                ebx
            //   57                   | push                edi
            //   ff75fc               | push                dword ptr [ebp - 4]
            //   8b3d????????         |                     

        $sequence_3 = { ff15???????? 68???????? 8d852cf8ffff 50 ffb528f8ffff e8???????? }
            // n = 6, score = 100
            //   ff15????????         |                     
            //   68????????           |                     
            //   8d852cf8ffff         | lea                 eax, [ebp - 0x7d4]
            //   50                   | push                eax
            //   ffb528f8ffff         | push                dword ptr [ebp - 0x7d8]
            //   e8????????           |                     

        $sequence_4 = { 68???????? 68???????? 68???????? 8d45fc 50 8d45b8 }
            // n = 6, score = 100
            //   68????????           |                     
            //   68????????           |                     
            //   68????????           |                     
            //   8d45fc               | lea                 eax, [ebp - 4]
            //   50                   | push                eax
            //   8d45b8               | lea                 eax, [ebp - 0x48]

        $sequence_5 = { e8???????? 83c408 8bf0 ff7704 ff15???????? 85f6 7414 }
            // n = 7, score = 100
            //   e8????????           |                     
            //   83c408               | add                 esp, 8
            //   8bf0                 | mov                 esi, eax
            //   ff7704               | push                dword ptr [edi + 4]
            //   ff15????????         |                     
            //   85f6                 | test                esi, esi
            //   7414                 | je                  0x16

        $sequence_6 = { c1f806 6bc930 8b048560dd4100 f644082801 7406 8b440818 5d }
            // n = 7, score = 100
            //   c1f806               | sar                 eax, 6
            //   6bc930               | imul                ecx, ecx, 0x30
            //   8b048560dd4100       | mov                 eax, dword ptr [eax*4 + 0x41dd60]
            //   f644082801           | test                byte ptr [eax + ecx + 0x28], 1
            //   7406                 | je                  8
            //   8b440818             | mov                 eax, dword ptr [eax + ecx + 0x18]
            //   5d                   | pop                 ebp

        $sequence_7 = { 83c410 ba03010000 85c0 0f44ca 8bc1 }
            // n = 5, score = 100
            //   83c410               | add                 esp, 0x10
            //   ba03010000           | mov                 edx, 0x103
            //   85c0                 | test                eax, eax
            //   0f44ca               | cmove               ecx, edx
            //   8bc1                 | mov                 eax, ecx

        $sequence_8 = { 56 e8???????? 83c408 85c0 7429 ffb5f0fdffff e8???????? }
            // n = 7, score = 100
            //   56                   | push                esi
            //   e8????????           |                     
            //   83c408               | add                 esp, 8
            //   85c0                 | test                eax, eax
            //   7429                 | je                  0x2b
            //   ffb5f0fdffff         | push                dword ptr [ebp - 0x210]
            //   e8????????           |                     

        $sequence_9 = { 6a03 68???????? e8???????? 8145e800403d7f 8d45e8 8155ec5b020000 }
            // n = 6, score = 100
            //   6a03                 | push                3
            //   68????????           |                     
            //   e8????????           |                     
            //   8145e800403d7f       | add                 dword ptr [ebp - 0x18], 0x7f3d4000
            //   8d45e8               | lea                 eax, [ebp - 0x18]
            //   8155ec5b020000       | adc                 dword ptr [ebp - 0x14], 0x25b

    condition:
        7 of them and filesize < 294912
}