rule win_makop_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2023-12-06"
        version = "1"
        description = "Detects win.makop."
        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.makop"
        malpedia_rule_date = "20231130"
        malpedia_hash = "fc8a0e9f343f6d6ded9e7df1a64dac0cc68d7351"
        malpedia_version = "20230808"
        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 = { 55 8bec 83e4f8 81ec10040000 53 55 56 }
            // n = 7, score = 100
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp
            //   83e4f8               | and                 esp, 0xfffffff8
            //   81ec10040000         | sub                 esp, 0x410
            //   53                   | push                ebx
            //   55                   | push                ebp
            //   56                   | push                esi

        $sequence_1 = { 8b84244c010000 8bcb 51 8b8c244c010000 52 50 51 }
            // n = 7, score = 100
            //   8b84244c010000       | mov                 eax, dword ptr [esp + 0x14c]
            //   8bcb                 | mov                 ecx, ebx
            //   51                   | push                ecx
            //   8b8c244c010000       | mov                 ecx, dword ptr [esp + 0x14c]
            //   52                   | push                edx
            //   50                   | push                eax
            //   51                   | push                ecx

        $sequence_2 = { 117c241c 8bb840080000 017c2420 8bb844080000 117c2424 8b8050080000 3bc3 }
            // n = 7, score = 100
            //   117c241c             | adc                 dword ptr [esp + 0x1c], edi
            //   8bb840080000         | mov                 edi, dword ptr [eax + 0x840]
            //   017c2420             | add                 dword ptr [esp + 0x20], edi
            //   8bb844080000         | mov                 edi, dword ptr [eax + 0x844]
            //   117c2424             | adc                 dword ptr [esp + 0x24], edi
            //   8b8050080000         | mov                 eax, dword ptr [eax + 0x850]
            //   3bc3                 | cmp                 eax, ebx

        $sequence_3 = { 3d11010000 0f8567030000 0fb7442444 0517fcffff 83f806 0f8754030000 ff24859c4f4000 }
            // n = 7, score = 100
            //   3d11010000           | cmp                 eax, 0x111
            //   0f8567030000         | jne                 0x36d
            //   0fb7442444           | movzx               eax, word ptr [esp + 0x44]
            //   0517fcffff           | add                 eax, 0xfffffc17
            //   83f806               | cmp                 eax, 6
            //   0f8754030000         | ja                  0x35a
            //   ff24859c4f4000       | jmp                 dword ptr [eax*4 + 0x404f9c]

        $sequence_4 = { 53 ff15???????? 85c0 0f84f1000000 6a00 8d442418 }
            // n = 6, score = 100
            //   53                   | push                ebx
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax
            //   0f84f1000000         | je                  0xf7
            //   6a00                 | push                0
            //   8d442418             | lea                 eax, [esp + 0x18]

        $sequence_5 = { 8d442418 50 51 e8???????? 85c0 0f85cb000000 }
            // n = 6, score = 100
            //   8d442418             | lea                 eax, [esp + 0x18]
            //   50                   | push                eax
            //   51                   | push                ecx
            //   e8????????           |                     
            //   85c0                 | test                eax, eax
            //   0f85cb000000         | jne                 0xd1

        $sequence_6 = { bb01000000 395d08 7571 b8???????? 668b08 83c002 6685c9 }
            // n = 7, score = 100
            //   bb01000000           | mov                 ebx, 1
            //   395d08               | cmp                 dword ptr [ebp + 8], ebx
            //   7571                 | jne                 0x73
            //   b8????????           |                     
            //   668b08               | mov                 cx, word ptr [eax]
            //   83c002               | add                 eax, 2
            //   6685c9               | test                cx, cx

        $sequence_7 = { 5e 5b 83c41c c3 ff15???????? 50 }
            // n = 6, score = 100
            //   5e                   | pop                 esi
            //   5b                   | pop                 ebx
            //   83c41c               | add                 esp, 0x1c
            //   c3                   | ret                 
            //   ff15????????         |                     
            //   50                   | push                eax

        $sequence_8 = { 33db 3bf3 740f 56 895e18 895e1c }
            // n = 6, score = 100
            //   33db                 | xor                 ebx, ebx
            //   3bf3                 | cmp                 esi, ebx
            //   740f                 | je                  0x11
            //   56                   | push                esi
            //   895e18               | mov                 dword ptr [esi + 0x18], ebx
            //   895e1c               | mov                 dword ptr [esi + 0x1c], ebx

        $sequence_9 = { 895c241c 895c2420 895c2424 745e 90 8b06 }
            // n = 6, score = 100
            //   895c241c             | mov                 dword ptr [esp + 0x1c], ebx
            //   895c2420             | mov                 dword ptr [esp + 0x20], ebx
            //   895c2424             | mov                 dword ptr [esp + 0x24], ebx
            //   745e                 | je                  0x60
            //   90                   | nop                 
            //   8b06                 | mov                 eax, dword ptr [esi]

    condition:
        7 of them and filesize < 107520
}

rule win_makop_w0 {
    meta:
        description = "Detects MAKOP ransomware payload"
        author = "@VK_Intel"
        reference = "https://twitter.com/VK_Intel/status/1242177227682390017"
        tlp = "white"
        date = "2020-03-23"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.makop"
        malpedia_version = "20200325"
        malpedia_sharing = "TLP:WHITE"
        malpedia_license = ""

    strings:
        $str1 = "-%08X"
        $str2 = "MPR.dll"
        $str3 = "\\*.*" wide

        $dec1 = { 8b ?? ?? 6a 08 8d ?? ?? ?? 52 8d ?? ?? ?? 50 e8 ?? ?? ?? ?? 66 ?? ?? ?? ?? 66 ?? ?? ?? ?? 83 c4 0c 66 3b c1 76 ?? 0f b7 c9 0f b7 f8 2b f9 74 ?? 57 6a 00 ff ?? ?? ?? ?? ?? 50 ff ?? ?? ?? ?? ?? 8b d8 85 db 74 ?? 0f ?? ?? ?? ?? 03 ?? ?? 57 52 53 e8 ?? ?? ?? ?? 83 c4 0c 8d ?? ?? 55 ff ?? ?? ?? ?? ?? e8 ?? ?? ?? ?? 84 c0 74 ?? 8b ?? ?? ?? 50 53 6a 00 6a 00 89 ?? 8b ?? ?? 6a 00 50 ff ?? ?? ?? ?? ?? 85 c0 75 ?? ff ?? ?? ?? ?? ?? 50 e8 ?? ?? ?? ?? 83 c4 04 33 c0 5f 5e 5d 5b 83 c4 0c c2 08 00}
        $start = {55 8b ec 83 e4 f8 a1 ?? ?? ?? ?? 81 ec 64 02 00 00 85 c0 53 56 57 74 ?? 6a 00 50 ff ?? ?? ?? ?? ?? 85 c0 0f ?? ?? ?? ?? ?? 8b ?? ?? 0f ?? ?? ?? 8b ?? ?? 51 e8 ?? ?? ?? ?? 83 c4 04 84 c0 0f ?? ?? ?? ?? ?? 8b ?? ?? 8d ?? ?? 8d ?? ?? 85 c0 0f ?? ?? ?? ?? ?? 50 6a 00 ff ?? ?? ?? ?? ?? 50 ff ?? ?? ?? ?? ?? 8b f0 85 f6 0f ?? ?? ?? ?? ?? 8b ?? ?? 80 ?? ?? ?? 75 ?? 81 fb fa 00 00 00 72 ?? 8b ?? ?? ?? ?? ?? 8b de e8 ?? ?? ?? ?? 8b ?? ?? 8b ?? ?? 83 c7 04 8d ?? ?? e8 ?? ?? ?? ?? 8b ?? ?? 8d ?? ?? ?? bf 05 00 00 00 eb ??}

    condition:
        ( uint16(0) == 0x5a4d and
        ( 4 of them )
        ) or ( all of them )
}