rule win_appleseed_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2022-11-21"
        version = "1"
        description = "Detects win.appleseed."
        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.appleseed"
        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 = { 488d93a00f0000 488bcb e8???????? 448b8374af0100 8b9370af0100 488d0d20040200 e8???????? }
            // n = 7, score = 100
            //   488d93a00f0000       | inc                 ebp
            //   488bcb               | xor                 eax, eax
            //   e8????????           |                     
            //   448b8374af0100       | dec                 eax
            //   8b9370af0100         | lea                 edx, [ebp + 0x60]
            //   488d0d20040200       | dec                 eax
            //   e8????????           |                     

        $sequence_1 = { 4c8bc0 418bd6 498bcc e8???????? 8bd8 448bc0 }
            // n = 6, score = 100
            //   4c8bc0               | mov                 byte ptr [esp + 0x50], 0
            //   418bd6               | inc                 ebp
            //   498bcc               | xor                 eax, eax
            //   e8????????           |                     
            //   8bd8                 | dec                 eax
            //   448bc0               | mov                 edx, eax

        $sequence_2 = { 488d05697e0100 c3 4883ec28 4885c9 }
            // n = 4, score = 100
            //   488d05697e0100       | inc                 esp
            //   c3                   | mov                 eax, esi
            //   4883ec28             | xor                 edx, edx
            //   4885c9               | dec                 eax

        $sequence_3 = { 4a8b8ce900670300 498bd4 48897c2420 488b0c0e ff15???????? }
            // n = 5, score = 100
            //   4a8b8ce900670300     | mov                 dword ptr [esp + 0x20], ecx
            //   498bd4               | inc                 ecx
            //   48897c2420           | mov                 ecx, 1
            //   488b0c0e             | inc                 ebp
            //   ff15????????         |                     

        $sequence_4 = { 448bc6 442bc0 488b442450 488d0d44d40100 }
            // n = 4, score = 100
            //   448bc6               | dec                 eax
            //   442bc0               | lea                 ebp, [eax - 0xc8]
            //   488b442450           | dec                 eax
            //   488d0d44d40100       | sub                 esp, 0x1a0

        $sequence_5 = { 803c3a00 75f7 488d4c2450 4c8bc7 e8???????? }
            // n = 5, score = 100
            //   803c3a00             | mov                 ecx, dword ptr [ebp + 0x48]
            //   75f7                 | nop                 
            //   488d4c2450           | dec                 eax
            //   4c8bc7               | cmp                 dword ptr [ebp + 0xa0], 0x10
            //   e8????????           |                     

        $sequence_6 = { e8???????? 85c0 0f8555ffffff 448b742438 e9???????? 488bcf ff15???????? }
            // n = 7, score = 100
            //   e8????????           |                     
            //   85c0                 | je                  0x1c5b
            //   0f8555ffffff         | dec                 eax
            //   448b742438           | add                 dword ptr [edi + 8], 0x20
            //   e9????????           |                     
            //   488bcf               | dec                 eax
            //   ff15????????         |                     

        $sequence_7 = { 7411 83caff 488bc8 ff15???????? bf01000000 48837b1810 }
            // n = 6, score = 100
            //   7411                 | ret                 
            //   83caff               | dec                 esp
            //   488bc8               | lea                 edx, [0x1d4dd]
            //   ff15????????         |                     
            //   bf01000000           | xor                 edx, edx
            //   48837b1810           | dec                 ebp

        $sequence_8 = { 488d15991b0200 488d4db8 e8???????? 90 488d55d8 488bc8 e8???????? }
            // n = 7, score = 100
            //   488d15991b0200       | cmp                 edx, eax
            //   488d4db8             | ja                  0x138c
            //   e8????????           |                     
            //   90                   | dec                 esp
            //   488d55d8             | lea                 edx, [0xfffe50e2]
            //   488bc8               | inc                 esp
            //   e8????????           |                     

        $sequence_9 = { ba01000000 488d4dd8 e8???????? 440fb67dd4 4983c602 48ffc7 }
            // n = 6, score = 100
            //   ba01000000           | xor                 edx, edx
            //   488d4dd8             | inc                 ecx
            //   e8????????           |                     
            //   440fb67dd4           | mov                 eax, 0x103
            //   4983c602             | dec                 eax
            //   48ffc7               | mov                 dword ptr [esp + 0x140], eax

    condition:
        7 of them and filesize < 497664
}

rule win_appleseed_w0 {
    meta:
        author = "KrCERT/CC Profound Analysis Team"
        date = "2020-12-4"
        info = "Operation MUZABI"
        hash = "43cc6d190238e851d33066cbe9be9ac8"
        hash = "fd10bd6013aabadbcb9edb8a23ba7331"
        hash = "16231e2e8991c60a42f293e0c33ff801"
        hash = "89fff6645013008cda57f88639b92990"
        hash = "030e2f992cbc4e61f0d5c994779caf3b"
        hash = "3620c22671641fbf32cf496b118b85f6"
        hash = "4876fc88c361743a1220a7b161f8f06f"
        hash = "94b8a0e4356d0202dc61046e3d8bdfe0"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.appleseed"
        malpedia_rule_date = "20201015"
        malpedia_version = "20201015"
        malpedia_license = "CC NC-BY-SA 4.0"
        malpedia_sharing = "TLP:WHITE"

    strings:
        $appleseed_str1 = {0f 8? ?? (00|01) 00 00 [0-1] 83 f? 20 0f 8? (01|00) 00 00}
        $appleseed_str2 = {88 45 [0-15] 0f b6 44 ?? 01}
        $appleseed_str3 = {83 f? 10 [0-5] 83 e? 10}
        $appleseed_key1 = {89 04 ?9 [0-6] ff 34 ?? e8 [10-16] 89 0c 98 8b ?? 0c [0-3] ff 34 98}
        $appleseed_key2 = {83 f? 10 [0-10] 32 4c 05 ?? ?? 88 4c ?? 0f}
        $appleseed_key3 = {89 04 ?9 49 83 ?? 04 48 ?? ?? 10 8b 0c a8 e8 [0-10] 48 8b ?? ?8}
        $seed_str1 = {44 0f b6 44 3d c0 45 32 c7 44 32 45 d4}
        $seed_str2 = {0f b6 44 3? ?? [0-25] 83 c4 0c}
        $seed_str3 = {32 45 c? ?? ?? ?? 32 45 e?}

    condition: 
            uint16(0) == 0x5a4d
        and
            filesize < 400KB
        and
            (2 of ($appleseed_str*))
        and
            (1 of ($seed_str*))
        and
            (1 of ($appleseed_key*))
}