rule win_buer_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2023-03-28"
        version = "1"
        description = "Detects win.buer."
        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.buer"
        malpedia_rule_date = "20230328"
        malpedia_hash = "9d2d75cef573c1c2d861f5197df8f563b05a305d"
        malpedia_version = "20230407"
        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 = { 85ff 7504 8bc2 eb19 33c0 }
            // n = 5, score = 1100
            //   85ff                 | test                edi, edi
            //   7504                 | jne                 6
            //   8bc2                 | mov                 eax, edx
            //   eb19                 | jmp                 0x1b
            //   33c0                 | xor                 eax, eax

        $sequence_1 = { 8bec 81ec2c010000 53 8bd9 }
            // n = 4, score = 1100
            //   8bec                 | mov                 ebp, esp
            //   81ec2c010000         | sub                 esp, 0x12c
            //   53                   | push                ebx
            //   8bd9                 | mov                 ebx, ecx

        $sequence_2 = { 8945f8 ff15???????? 59 59 85c0 }
            // n = 5, score = 1100
            //   8945f8               | mov                 dword ptr [ebp - 8], eax
            //   ff15????????         |                     
            //   59                   | pop                 ecx
            //   59                   | pop                 ecx
            //   85c0                 | test                eax, eax

        $sequence_3 = { 03c2 8b55e8 015158 8b55d8 894148 8b45dc 03c6 }
            // n = 7, score = 1100
            //   03c2                 | add                 eax, edx
            //   8b55e8               | mov                 edx, dword ptr [ebp - 0x18]
            //   015158               | add                 dword ptr [ecx + 0x58], edx
            //   8b55d8               | mov                 edx, dword ptr [ebp - 0x28]
            //   894148               | mov                 dword ptr [ecx + 0x48], eax
            //   8b45dc               | mov                 eax, dword ptr [ebp - 0x24]
            //   03c6                 | add                 eax, esi

        $sequence_4 = { 7d0f 8a0c46 880c18 40 3bc2 7cf1 }
            // n = 6, score = 1100
            //   7d0f                 | jge                 0x11
            //   8a0c46               | mov                 cl, byte ptr [esi + eax*2]
            //   880c18               | mov                 byte ptr [eax + ebx], cl
            //   40                   | inc                 eax
            //   3bc2                 | cmp                 eax, edx
            //   7cf1                 | jl                  0xfffffff3

        $sequence_5 = { 8b00 8b4010 8945fc 61 8b45fc }
            // n = 5, score = 1100
            //   8b00                 | mov                 eax, dword ptr [eax]
            //   8b4010               | mov                 eax, dword ptr [eax + 0x10]
            //   8945fc               | mov                 dword ptr [ebp - 4], eax
            //   61                   | popal               
            //   8b45fc               | mov                 eax, dword ptr [ebp - 4]

        $sequence_6 = { 8b7b50 8b4340 0345f8 8b5b54 }
            // n = 4, score = 1100
            //   8b7b50               | mov                 edi, dword ptr [ebx + 0x50]
            //   8b4340               | mov                 eax, dword ptr [ebx + 0x40]
            //   0345f8               | add                 eax, dword ptr [ebp - 8]
            //   8b5b54               | mov                 ebx, dword ptr [ebx + 0x54]

        $sequence_7 = { 7cf1 eb02 33c0 5f 5e }
            // n = 5, score = 1100
            //   7cf1                 | jl                  0xfffffff3
            //   eb02                 | jmp                 4
            //   33c0                 | xor                 eax, eax
            //   5f                   | pop                 edi
            //   5e                   | pop                 esi

        $sequence_8 = { c1ea10 b9???????? 89442461 88542467 }
            // n = 4, score = 300
            //   c1ea10               | shr                 edx, 0x10
            //   b9????????           |                     
            //   89442461             | mov                 dword ptr [esp + 0x61], eax
            //   88542467             | mov                 byte ptr [esp + 0x67], dl

        $sequence_9 = { e8???????? 0f0b b92c000000 ba01000000 e8???????? 0f0b 89f9 }
            // n = 7, score = 300
            //   e8????????           |                     
            //   0f0b                 | ud2                 
            //   b92c000000           | mov                 ecx, 0x2c
            //   ba01000000           | mov                 edx, 1
            //   e8????????           |                     
            //   0f0b                 | ud2                 
            //   89f9                 | mov                 ecx, edi

        $sequence_10 = { c1e808 c1e104 c1ea1a 03542428 }
            // n = 4, score = 300
            //   c1e808               | shr                 eax, 8
            //   c1e104               | shl                 ecx, 4
            //   c1ea1a               | shr                 edx, 0x1a
            //   03542428             | add                 edx, dword ptr [esp + 0x28]

        $sequence_11 = { c1e615 2974245c 8bf3 8b9c24c4000000 }
            // n = 4, score = 300
            //   c1e615               | shl                 esi, 0x15
            //   2974245c             | sub                 dword ptr [esp + 0x5c], esi
            //   8bf3                 | mov                 esi, ebx
            //   8b9c24c4000000       | mov                 ebx, dword ptr [esp + 0xc4]

        $sequence_12 = { c1e808 c1e106 03c8 8bc1 }
            // n = 4, score = 300
            //   c1e808               | shr                 eax, 8
            //   c1e106               | shl                 ecx, 6
            //   03c8                 | add                 ecx, eax
            //   8bc1                 | mov                 eax, ecx

        $sequence_13 = { e8???????? 0f0b b9???????? ba43000000 68???????? eb0f }
            // n = 6, score = 300
            //   e8????????           |                     
            //   0f0b                 | ud2                 
            //   b9????????           |                     
            //   ba43000000           | mov                 edx, 0x43
            //   68????????           |                     
            //   eb0f                 | jmp                 0x11

        $sequence_14 = { c1e808 8d04e8 89442440 c1e808 }
            // n = 4, score = 300
            //   c1e808               | shr                 eax, 8
            //   8d04e8               | lea                 eax, [eax + ebp*8]
            //   89442440             | mov                 dword ptr [esp + 0x40], eax
            //   c1e808               | shr                 eax, 8

        $sequence_15 = { c3 e8???????? 0f0b 8b4c2408 }
            // n = 4, score = 300
            //   c3                   | ret                 
            //   e8????????           |                     
            //   0f0b                 | ud2                 
            //   8b4c2408             | mov                 ecx, dword ptr [esp + 8]

    condition:
        7 of them and filesize < 3031040
}