rule win_webc2_head_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2020-12-22"
        version = "1"
        description = "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.webc2_head"
        malpedia_rule_date = "20201222"
        malpedia_hash = "30354d830a29f0fbd3714d93d94dea941d77a130"
        malpedia_version = "20201023"
        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 = { 8ac8 80c120 8888e0b84000 eb1f }
            // n = 4, score = 100
            //   8ac8                 | mov                 cl, al
            //   80c120               | add                 cl, 0x20
            //   8888e0b84000         | mov                 byte ptr [eax + 0x40b8e0], cl
            //   eb1f                 | jmp                 0x21

        $sequence_1 = { f3a5 8bc8 33c0 83e103 f3a4 8d7a02 }
            // n = 6, score = 100
            //   f3a5                 | rep movsd           dword ptr es:[edi], dword ptr [esi]
            //   8bc8                 | mov                 ecx, eax
            //   33c0                 | xor                 eax, eax
            //   83e103               | and                 ecx, 3
            //   f3a4                 | rep movsb           byte ptr es:[edi], byte ptr [esi]
            //   8d7a02               | lea                 edi, [edx + 2]

        $sequence_2 = { 7505 b83f000000 c3 81ec6c010000 }
            // n = 4, score = 100
            //   7505                 | jne                 7
            //   b83f000000           | mov                 eax, 0x3f
            //   c3                   | ret                 
            //   81ec6c010000         | sub                 esp, 0x16c

        $sequence_3 = { 5f 5e b802000000 5b 81c46c010000 }
            // n = 5, score = 100
            //   5f                   | pop                 edi
            //   5e                   | pop                 esi
            //   b802000000           | mov                 eax, 2
            //   5b                   | pop                 ebx
            //   81c46c010000         | add                 esp, 0x16c

        $sequence_4 = { 89442418 895c2410 8944241c ff15???????? 85c0 0f84c9010000 }
            // n = 6, score = 100
            //   89442418             | mov                 dword ptr [esp + 0x18], eax
            //   895c2410             | mov                 dword ptr [esp + 0x10], ebx
            //   8944241c             | mov                 dword ptr [esp + 0x1c], eax
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax
            //   0f84c9010000         | je                  0x1cf

        $sequence_5 = { 8943fc 4a 894c2420 0f8550ffffff 8b542424 8b4c241c }
            // n = 6, score = 100
            //   8943fc               | mov                 dword ptr [ebx - 4], eax
            //   4a                   | dec                 edx
            //   894c2420             | mov                 dword ptr [esp + 0x20], ecx
            //   0f8550ffffff         | jne                 0xffffff56
            //   8b542424             | mov                 edx, dword ptr [esp + 0x24]
            //   8b4c241c             | mov                 ecx, dword ptr [esp + 0x1c]

        $sequence_6 = { 8d442414 53 50 8d8c24d4030000 6800020000 }
            // n = 5, score = 100
            //   8d442414             | lea                 eax, [esp + 0x14]
            //   53                   | push                ebx
            //   50                   | push                eax
            //   8d8c24d4030000       | lea                 ecx, [esp + 0x3d4]
            //   6800020000           | push                0x200

        $sequence_7 = { 0f8444030000 b900010000 33c0 bf???????? 68???????? f3ab 68???????? }
            // n = 7, score = 100
            //   0f8444030000         | je                  0x34a
            //   b900010000           | mov                 ecx, 0x100
            //   33c0                 | xor                 eax, eax
            //   bf????????           |                     
            //   68????????           |                     
            //   f3ab                 | rep stosd           dword ptr es:[edi], eax
            //   68????????           |                     

        $sequence_8 = { 7d09 8a8404ec000000 eb02 b03d 83fb02 }
            // n = 5, score = 100
            //   7d09                 | jge                 0xb
            //   8a8404ec000000       | mov                 al, byte ptr [esp + eax + 0xec]
            //   eb02                 | jmp                 4
            //   b03d                 | mov                 al, 0x3d
            //   83fb02               | cmp                 ebx, 2

        $sequence_9 = { 884502 7e2a b910000000 be???????? 8dbc2474010000 }
            // n = 5, score = 100
            //   884502               | mov                 byte ptr [ebp + 2], al
            //   7e2a                 | jle                 0x2c
            //   b910000000           | mov                 ecx, 0x10
            //   be????????           |                     
            //   8dbc2474010000       | lea                 edi, [esp + 0x174]

    condition:
        7 of them and filesize < 106496
}