rule win_khrat_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2022-11-21"
        version = "1"
        description = "Detects win.khrat."
        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.khrat"
        malpedia_rule_date = "20221118"
        malpedia_hash = "e0702e2e6d1d00da65c8a29a4ebacd0a4c59e1af"
        malpedia_version = "20221125"
        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 = { 59 5b c9 c20400 55 8bec 81c448feffff }
            // n = 7, score = 100
            //   59                   | pop                 ecx
            //   5b                   | pop                 ebx
            //   c9                   | leave               
            //   c20400               | ret                 4
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp
            //   81c448feffff         | add                 esp, 0xfffffe48

        $sequence_1 = { a3???????? 6a00 6800003000 6a00 6a04 6a00 }
            // n = 6, score = 100
            //   a3????????           |                     
            //   6a00                 | push                0
            //   6800003000           | push                0x300000
            //   6a00                 | push                0
            //   6a04                 | push                4
            //   6a00                 | push                0

        $sequence_2 = { 8985e8fdffff ffb5e8fdffff e8???????? 3d0180ffff 0f85b1070000 68ff000000 }
            // n = 6, score = 100
            //   8985e8fdffff         | mov                 dword ptr [ebp - 0x218], eax
            //   ffb5e8fdffff         | push                dword ptr [ebp - 0x218]
            //   e8????????           |                     
            //   3d0180ffff           | cmp                 eax, 0xffff8001
            //   0f85b1070000         | jne                 0x7b7
            //   68ff000000           | push                0xff

        $sequence_3 = { 8f05???????? ff730b 8f05???????? ff730f 8f05???????? 6a00 6a00 }
            // n = 7, score = 100
            //   8f05????????         |                     
            //   ff730b               | push                dword ptr [ebx + 0xb]
            //   8f05????????         |                     
            //   ff730f               | push                dword ptr [ebx + 0xf]
            //   8f05????????         |                     
            //   6a00                 | push                0
            //   6a00                 | push                0

        $sequence_4 = { e8???????? 8d85d4fdffff 50 ffb5d0f9ffff }
            // n = 4, score = 100
            //   e8????????           |                     
            //   8d85d4fdffff         | lea                 eax, [ebp - 0x22c]
            //   50                   | push                eax
            //   ffb5d0f9ffff         | push                dword ptr [ebp - 0x630]

        $sequence_5 = { c20800 55 8bec 81c48cfbffff 8d1d10520010 }
            // n = 5, score = 100
            //   c20800               | ret                 8
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp
            //   81c48cfbffff         | add                 esp, 0xfffffb8c
            //   8d1d10520010         | lea                 ebx, [0x10005210]

        $sequence_6 = { 57 ffb594fbffff e8???????? eb08 c70300000000 }
            // n = 5, score = 100
            //   57                   | push                edi
            //   ffb594fbffff         | push                dword ptr [ebp - 0x46c]
            //   e8????????           |                     
            //   eb08                 | jmp                 0xa
            //   c70300000000         | mov                 dword ptr [ebx], 0

        $sequence_7 = { 50 e8???????? 6a00 6a07 8d85c0fbffff 50 }
            // n = 6, score = 100
            //   50                   | push                eax
            //   e8????????           |                     
            //   6a00                 | push                0
            //   6a07                 | push                7
            //   8d85c0fbffff         | lea                 eax, [ebp - 0x440]
            //   50                   | push                eax

        $sequence_8 = { 0bc0 7405 a3???????? 5b }
            // n = 4, score = 100
            //   0bc0                 | or                  eax, eax
            //   7405                 | je                  7
            //   a3????????           |                     
            //   5b                   | pop                 ebx

        $sequence_9 = { 66c746043800 66c746063800 66c746083500 66c7460a3100 66c7460c3200 66c7460e3000 66c746104500 }
            // n = 7, score = 100
            //   66c746043800         | mov                 word ptr [esi + 4], 0x38
            //   66c746063800         | mov                 word ptr [esi + 6], 0x38
            //   66c746083500         | mov                 word ptr [esi + 8], 0x35
            //   66c7460a3100         | mov                 word ptr [esi + 0xa], 0x31
            //   66c7460c3200         | mov                 word ptr [esi + 0xc], 0x32
            //   66c7460e3000         | mov                 word ptr [esi + 0xe], 0x30
            //   66c746104500         | mov                 word ptr [esi + 0x10], 0x45

    condition:
        7 of them and filesize < 57344
}