rule win_killav_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2022-08-05"
        version = "1"
        description = "Detects win.killav."
        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.killav"
        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 = { 8a0e 0fb6c1 0fbe80e0a24300 85c0 7510 }
            // n = 5, score = 100
            //   8a0e                 | mov                 cl, byte ptr [esi]
            //   0fb6c1               | movzx               eax, cl
            //   0fbe80e0a24300       | movsx               eax, byte ptr [eax + 0x43a2e0]
            //   85c0                 | test                eax, eax
            //   7510                 | jne                 0x12

        $sequence_1 = { c745ec07000000 668945d8 e8???????? 8d45d8 c645fc09 50 8d4dd0 }
            // n = 7, score = 100
            //   c745ec07000000       | mov                 dword ptr [ebp - 0x14], 7
            //   668945d8             | mov                 word ptr [ebp - 0x28], ax
            //   e8????????           |                     
            //   8d45d8               | lea                 eax, [ebp - 0x28]
            //   c645fc09             | mov                 byte ptr [ebp - 4], 9
            //   50                   | push                eax
            //   8d4dd0               | lea                 ecx, [ebp - 0x30]

        $sequence_2 = { 99 8945f8 8b4de0 8b45e8 8b0c8d70ba4300 f644082804 7416 }
            // n = 7, score = 100
            //   99                   | cdq                 
            //   8945f8               | mov                 dword ptr [ebp - 8], eax
            //   8b4de0               | mov                 ecx, dword ptr [ebp - 0x20]
            //   8b45e8               | mov                 eax, dword ptr [ebp - 0x18]
            //   8b0c8d70ba4300       | mov                 ecx, dword ptr [ecx*4 + 0x43ba70]
            //   f644082804           | test                byte ptr [eax + ecx + 0x28], 4
            //   7416                 | je                  0x18

        $sequence_3 = { 0f82e9feffff eb23 8b4df0 8b0c8d70ba4300 8a443928 }
            // n = 5, score = 100
            //   0f82e9feffff         | jb                  0xfffffeef
            //   eb23                 | jmp                 0x25
            //   8b4df0               | mov                 ecx, dword ptr [ebp - 0x10]
            //   8b0c8d70ba4300       | mov                 ecx, dword ptr [ecx*4 + 0x43ba70]
            //   8a443928             | mov                 al, byte ptr [ecx + edi + 0x28]

        $sequence_4 = { ff5004 56 8d4dd8 e8???????? c645fc02 8b0d???????? }
            // n = 6, score = 100
            //   ff5004               | call                dword ptr [eax + 4]
            //   56                   | push                esi
            //   8d4dd8               | lea                 ecx, [ebp - 0x28]
            //   e8????????           |                     
            //   c645fc02             | mov                 byte ptr [ebp - 4], 2
            //   8b0d????????         |                     

        $sequence_5 = { 7603 6a26 58 0fb60c855ed34200 0fb634855fd34200 8bf9 898598f8ffff }
            // n = 7, score = 100
            //   7603                 | jbe                 5
            //   6a26                 | push                0x26
            //   58                   | pop                 eax
            //   0fb60c855ed34200     | movzx               ecx, byte ptr [eax*4 + 0x42d35e]
            //   0fb634855fd34200     | movzx               esi, byte ptr [eax*4 + 0x42d35f]
            //   8bf9                 | mov                 edi, ecx
            //   898598f8ffff         | mov                 dword ptr [ebp - 0x768], eax

        $sequence_6 = { 668945d8 e8???????? 8d45d8 c645fc25 50 }
            // n = 5, score = 100
            //   668945d8             | mov                 word ptr [ebp - 0x28], ax
            //   e8????????           |                     
            //   8d45d8               | lea                 eax, [ebp - 0x28]
            //   c645fc25             | mov                 byte ptr [ebp - 4], 0x25
            //   50                   | push                eax

        $sequence_7 = { 5d c3 837d08ff 0f845d57ffff e9???????? }
            // n = 5, score = 100
            //   5d                   | pop                 ebp
            //   c3                   | ret                 
            //   837d08ff             | cmp                 dword ptr [ebp + 8], -1
            //   0f845d57ffff         | je                  0xffff5763
            //   e9????????           |                     

        $sequence_8 = { 57 8d4dc8 8975d0 e8???????? 8975fc }
            // n = 5, score = 100
            //   57                   | push                edi
            //   8d4dc8               | lea                 ecx, [ebp - 0x38]
            //   8975d0               | mov                 dword ptr [ebp - 0x30], esi
            //   e8????????           |                     
            //   8975fc               | mov                 dword ptr [ebp - 4], esi

        $sequence_9 = { 2bc1 83c0fc 83f81f 0f87961e0000 }
            // n = 4, score = 100
            //   2bc1                 | sub                 eax, ecx
            //   83c0fc               | add                 eax, -4
            //   83f81f               | cmp                 eax, 0x1f
            //   0f87961e0000         | ja                  0x1e9c

    condition:
        7 of them and filesize < 517120
}