rule win_shimrat_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2022-08-05"
        version = "1"
        description = "Detects win.shimrat."
        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.shimrat"
        malpedia_rule_date = "20220805"
        malpedia_hash = "6ec06c64bcfdbeda64eff021c766b4ce34542b71"
        malpedia_version = "20220808"
        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 = { 85c0 7535 83ec0c 8d45f0 }
            // n = 4, score = 100
            //   85c0                 | test                eax, eax
            //   7535                 | jne                 0x37
            //   83ec0c               | sub                 esp, 0xc
            //   8d45f0               | lea                 eax, [ebp - 0x10]

        $sequence_1 = { 33c0 8901 894104 894108 c3 56 }
            // n = 6, score = 100
            //   33c0                 | xor                 eax, eax
            //   8901                 | mov                 dword ptr [ecx], eax
            //   894104               | mov                 dword ptr [ecx + 4], eax
            //   894108               | mov                 dword ptr [ecx + 8], eax
            //   c3                   | ret                 
            //   56                   | push                esi

        $sequence_2 = { ff750c d1f8 40 50 ff7508 }
            // n = 5, score = 100
            //   ff750c               | push                dword ptr [ebp + 0xc]
            //   d1f8                 | sar                 eax, 1
            //   40                   | inc                 eax
            //   50                   | push                eax
            //   ff7508               | push                dword ptr [ebp + 8]

        $sequence_3 = { 83c414 50 8d4f6c e8???????? 660fbe06 0fb7c0 8945fc }
            // n = 7, score = 100
            //   83c414               | add                 esp, 0x14
            //   50                   | push                eax
            //   8d4f6c               | lea                 ecx, [edi + 0x6c]
            //   e8????????           |                     
            //   660fbe06             | movsx               ax, byte ptr [esi]
            //   0fb7c0               | movzx               eax, ax
            //   8945fc               | mov                 dword ptr [ebp - 4], eax

        $sequence_4 = { 56 ffd7 5f 5e c3 56 }
            // n = 6, score = 100
            //   56                   | push                esi
            //   ffd7                 | call                edi
            //   5f                   | pop                 edi
            //   5e                   | pop                 esi
            //   c3                   | ret                 
            //   56                   | push                esi

        $sequence_5 = { e8???????? 8b4d30 50 e8???????? 85c0 }
            // n = 5, score = 100
            //   e8????????           |                     
            //   8b4d30               | mov                 ecx, dword ptr [ebp + 0x30]
            //   50                   | push                eax
            //   e8????????           |                     
            //   85c0                 | test                eax, eax

        $sequence_6 = { ff75e8 ffd6 395dc8 7405 ff75c8 ffd6 8d4d18 }
            // n = 7, score = 100
            //   ff75e8               | push                dword ptr [ebp - 0x18]
            //   ffd6                 | call                esi
            //   395dc8               | cmp                 dword ptr [ebp - 0x38], ebx
            //   7405                 | je                  7
            //   ff75c8               | push                dword ptr [ebp - 0x38]
            //   ffd6                 | call                esi
            //   8d4d18               | lea                 ecx, [ebp + 0x18]

        $sequence_7 = { 8d45fc 56 50 e8???????? ff75fc e8???????? 0fb7c0 }
            // n = 7, score = 100
            //   8d45fc               | lea                 eax, [ebp - 4]
            //   56                   | push                esi
            //   50                   | push                eax
            //   e8????????           |                     
            //   ff75fc               | push                dword ptr [ebp - 4]
            //   e8????????           |                     
            //   0fb7c0               | movzx               eax, ax

        $sequence_8 = { 56 6a02 6a10 68ff010f00 e8???????? bf???????? 50 }
            // n = 7, score = 100
            //   56                   | push                esi
            //   6a02                 | push                2
            //   6a10                 | push                0x10
            //   68ff010f00           | push                0xf01ff
            //   e8????????           |                     
            //   bf????????           |                     
            //   50                   | push                eax

        $sequence_9 = { 7713 8d8550ffffff 68???????? 50 e8???????? 59 59 }
            // n = 7, score = 100
            //   7713                 | ja                  0x15
            //   8d8550ffffff         | lea                 eax, [ebp - 0xb0]
            //   68????????           |                     
            //   50                   | push                eax
            //   e8????????           |                     
            //   59                   | pop                 ecx
            //   59                   | pop                 ecx

    condition:
        7 of them and filesize < 65536
}