rule win_mailto_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.mailto"
        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 = { 8d4c2440 51 6a0f 8b4074 53 ffd0 8b7c2440 }
            // n = 7, score = 400
            //   8d4c2440             | lea                 ecx, [esp + 0x40]
            //   51                   | push                ecx
            //   6a0f                 | push                0xf
            //   8b4074               | mov                 eax, dword ptr [eax + 0x74]
            //   53                   | push                ebx
            //   ffd0                 | call                eax
            //   8b7c2440             | mov                 edi, dword ptr [esp + 0x40]

        $sequence_1 = { 747a 8bf2 89542414 89542410 }
            // n = 4, score = 400
            //   747a                 | je                  0x7c
            //   8bf2                 | mov                 esi, edx
            //   89542414             | mov                 dword ptr [esp + 0x14], edx
            //   89542410             | mov                 dword ptr [esp + 0x10], edx

        $sequence_2 = { 57 33ff 85f6 0f843e010000 8b5c2414 }
            // n = 5, score = 400
            //   57                   | push                edi
            //   33ff                 | xor                 edi, edi
            //   85f6                 | test                esi, esi
            //   0f843e010000         | je                  0x144
            //   8b5c2414             | mov                 ebx, dword ptr [esp + 0x14]

        $sequence_3 = { 0f84d0000000 c60009 e8???????? 8d4c2414 51 8b407c ffd0 }
            // n = 7, score = 400
            //   0f84d0000000         | je                  0xd6
            //   c60009               | mov                 byte ptr [eax], 9
            //   e8????????           |                     
            //   8d4c2414             | lea                 ecx, [esp + 0x14]
            //   51                   | push                ecx
            //   8b407c               | mov                 eax, dword ptr [eax + 0x7c]
            //   ffd0                 | call                eax

        $sequence_4 = { 83c408 3b7b10 72e5 8b4314 }
            // n = 4, score = 400
            //   83c408               | add                 esp, 8
            //   3b7b10               | cmp                 edi, dword ptr [ebx + 0x10]
            //   72e5                 | jb                  0xffffffe7
            //   8b4314               | mov                 eax, dword ptr [ebx + 0x14]

        $sequence_5 = { e8???????? 83c40c 85c0 741a 8b4f14 56 51 }
            // n = 7, score = 400
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc
            //   85c0                 | test                eax, eax
            //   741a                 | je                  0x1c
            //   8b4f14               | mov                 ecx, dword ptr [edi + 0x14]
            //   56                   | push                esi
            //   51                   | push                ecx

        $sequence_6 = { 57 6a20 e8???????? 8bf8 83c404 85ff 7429 }
            // n = 7, score = 400
            //   57                   | push                edi
            //   6a20                 | push                0x20
            //   e8????????           |                     
            //   8bf8                 | mov                 edi, eax
            //   83c404               | add                 esp, 4
            //   85ff                 | test                edi, edi
            //   7429                 | je                  0x2b

        $sequence_7 = { 7508 84c0 0f8491000000 57 56 e8???????? 83c408 }
            // n = 7, score = 400
            //   7508                 | jne                 0xa
            //   84c0                 | test                al, al
            //   0f8491000000         | je                  0x97
            //   57                   | push                edi
            //   56                   | push                esi
            //   e8????????           |                     
            //   83c408               | add                 esp, 8

        $sequence_8 = { 88461a 8bc3 c1f810 884e16 8bcd 88461b 8bc1 }
            // n = 7, score = 400
            //   88461a               | mov                 byte ptr [esi + 0x1a], al
            //   8bc3                 | mov                 eax, ebx
            //   c1f810               | sar                 eax, 0x10
            //   884e16               | mov                 byte ptr [esi + 0x16], cl
            //   8bcd                 | mov                 ecx, ebp
            //   88461b               | mov                 byte ptr [esi + 0x1b], al
            //   8bc1                 | mov                 eax, ecx

        $sequence_9 = { 8bc7 2bf7 b902000000 8d4010 0f104406f0 660fefc1 0f1140f0 }
            // n = 7, score = 400
            //   8bc7                 | mov                 eax, edi
            //   2bf7                 | sub                 esi, edi
            //   b902000000           | mov                 ecx, 2
            //   8d4010               | lea                 eax, [eax + 0x10]
            //   0f104406f0           | movups              xmm0, xmmword ptr [esi + eax - 0x10]
            //   660fefc1             | pxor                xmm0, xmm1
            //   0f1140f0             | movups              xmmword ptr [eax - 0x10], xmm0

    condition:
        7 of them and filesize < 180224
}