rule win_lookback_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2020-10-14"
        version = "1"
        description = "autogenerated rule brought to you by yara-signator"
        tool = "yara-signator v0.5.0"
        tool_config = "callsandjumps;datarefs;binvalue"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.lookback"
        malpedia_rule_date = "20201014"
        malpedia_hash = "a7e3bd57eaf12bf3ea29a863c041091ba3af9ac9"
        malpedia_version = "20201014"
        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 = { 66f3a7 7517 8b00 85c0 75dd }
            // n = 5, score = 100
            //   66f3a7               | repe cmpsd          dword ptr [esi], dword ptr es:[edi]
            //   7517                 | jne                 0x19
            //   8b00                 | mov                 eax, dword ptr [eax]
            //   85c0                 | test                eax, eax
            //   75dd                 | jne                 0xffffffdf

        $sequence_1 = { 53 55 8b2d???????? 56 8bb4241c010000 57 }
            // n = 6, score = 100
            //   53                   | push                ebx
            //   55                   | push                ebp
            //   8b2d????????         |                     
            //   56                   | push                esi
            //   8bb4241c010000       | mov                 esi, dword ptr [esp + 0x11c]
            //   57                   | push                edi

        $sequence_2 = { 55 8bec 51 53 c745fc00000000 b801000000 }
            // n = 6, score = 100
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp
            //   51                   | push                ecx
            //   53                   | push                ebx
            //   c745fc00000000       | mov                 dword ptr [ebp - 4], 0
            //   b801000000           | mov                 eax, 1

        $sequence_3 = { ffd3 a1???????? c644241300 3bc7 7477 a1???????? }
            // n = 6, score = 100
            //   ffd3                 | call                ebx
            //   a1????????           |                     
            //   c644241300           | mov                 byte ptr [esp + 0x13], 0
            //   3bc7                 | cmp                 eax, edi
            //   7477                 | je                  0x79
            //   a1????????           |                     

        $sequence_4 = { e8???????? 83f86f 7520 53 e8???????? 8b442414 50 }
            // n = 7, score = 100
            //   e8????????           |                     
            //   83f86f               | cmp                 eax, 0x6f
            //   7520                 | jne                 0x22
            //   53                   | push                ebx
            //   e8????????           |                     
            //   8b442414             | mov                 eax, dword ptr [esp + 0x14]
            //   50                   | push                eax

        $sequence_5 = { 57 57 a3???????? ffd6 8d542428 }
            // n = 5, score = 100
            //   57                   | push                edi
            //   57                   | push                edi
            //   a3????????           |                     
            //   ffd6                 | call                esi
            //   8d542428             | lea                 edx, [esp + 0x28]

        $sequence_6 = { 8b442410 45 83c204 3be8 }
            // n = 4, score = 100
            //   8b442410             | mov                 eax, dword ptr [esp + 0x10]
            //   45                   | inc                 ebp
            //   83c204               | add                 edx, 4
            //   3be8                 | cmp                 ebp, eax

        $sequence_7 = { 85c0 74a7 8b06 85c0 757b 6a18 }
            // n = 6, score = 100
            //   85c0                 | test                eax, eax
            //   74a7                 | je                  0xffffffa9
            //   8b06                 | mov                 eax, dword ptr [esi]
            //   85c0                 | test                eax, eax
            //   757b                 | jne                 0x7d
            //   6a18                 | push                0x18

        $sequence_8 = { 668b5004 66895504 53 e8???????? }
            // n = 4, score = 100
            //   668b5004             | mov                 dx, word ptr [eax + 4]
            //   66895504             | mov                 word ptr [ebp + 4], dx
            //   53                   | push                ebx
            //   e8????????           |                     

        $sequence_9 = { 8bcb 8bc3 c1f905 83e01f 8b0c8d80d47100 8d04c0 }
            // n = 6, score = 100
            //   8bcb                 | mov                 ecx, ebx
            //   8bc3                 | mov                 eax, ebx
            //   c1f905               | sar                 ecx, 5
            //   83e01f               | and                 eax, 0x1f
            //   8b0c8d80d47100       | mov                 ecx, dword ptr [ecx*4 + 0x71d480]
            //   8d04c0               | lea                 eax, [eax + eax*8]

    condition:
        7 of them and filesize < 131072
}