rule win_appleseed_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.appleseed"
        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 = { 488b4c2478 e8???????? 48c745900f000000 48895d88 c644247800 48837c246810 720a }
            // n = 7, score = 100
            //   488b4c2478           | nop                 
            //   e8????????           |                     
            //   48c745900f000000     | dec                 eax
            //   48895d88             | mov                 dword ptr [ebp - 0x60], 0xf
            //   c644247800           | dec                 esp
            //   48837c246810         | mov                 dword ptr [ebp - 0x68], esi
            //   720a                 | dec                 eax

        $sequence_1 = { 4883c420 5b c3 488d15c2c70100 488bcb }
            // n = 5, score = 100
            //   4883c420             | ret                 
            //   5b                   | dec                 eax
            //   c3                   | lea                 ecx, [0x26d1d]
            //   488d15c2c70100       | int3                
            //   488bcb               | ret                 

        $sequence_2 = { 57 4156 488d6c24c0 4881ec40010000 48c7442460feffffff 488b05???????? 4833c4 }
            // n = 7, score = 100
            //   57                   | mov                 dword ptr [ebp + 0x68], 0xf
            //   4156                 | mov                 byte ptr [ebp - 0x10], 0
            //   488d6c24c0           | dec                 ecx
            //   4881ec40010000       | or                  ecx, 0xffffffff
            //   48c7442460feffffff     | inc    ebp
            //   488b05????????       |                     
            //   4833c4               | xor                 eax, eax

        $sequence_3 = { e8???????? 90 488d542460 488d4c2440 e8???????? 90 4c8d05cb670200 }
            // n = 7, score = 100
            //   e8????????           |                     
            //   90                   | cmp                 dword ptr [ebp + 0x60], 0x10
            //   488d542460           | jb                  0x428
            //   488d4c2440           | inc                 ecx
            //   e8????????           |                     
            //   90                   | mov                 ecx, 0x104
            //   4c8d05cb670200       | dec                 esp

        $sequence_4 = { 48c745a00f000000 48897d98 c6458800 48837d0010 7209 }
            // n = 5, score = 100
            //   48c745a00f000000     | dec                 eax
            //   48897d98             | arpl                bx, cx
            //   c6458800             | dec                 esp
            //   48837d0010           | mov                 edi, eax
            //   7209                 | inc                 esp

        $sequence_5 = { 488945f8 488bf2 488bd9 4533ed 44896db0 }
            // n = 5, score = 100
            //   488945f8             | inc                 ebp
            //   488bf2               | xor                 eax, eax
            //   488bd9               | dec                 eax
            //   4533ed               | mov                 edx, eax
            //   44896db0             | mov                 byte ptr [ebp + 0xc0], 0

        $sequence_6 = { 488bcb 488bc3 488d15326f0100 48c1f805 83e11f 488b04c2 486bc958 }
            // n = 7, score = 100
            //   488bcb               | lea                 ecx, [ebp + 0x148]
            //   488bc3               | dec                 eax
            //   488d15326f0100       | mov                 dword ptr [ebp + 0x160], 0xf
            //   48c1f805             | dec                 eax
            //   83e11f               | mov                 dword ptr [ebp + 0x158], esi
            //   488b04c2             | mov                 byte ptr [ebp + 0x148], 0
            //   486bc958             | dec                 eax

        $sequence_7 = { 488b5c2430 4883c420 5f c3 488d0d1d6d0200 e8???????? }
            // n = 6, score = 100
            //   488b5c2430           | dec                 eax
            //   4883c420             | mov                 dword ptr [ecx + 0x6aff0], eax
            //   5f                   | jl                  0x32a
            //   c3                   | dec                 esp
            //   488d0d1d6d0200       | mov                 dword ptr [ebp - 0x60], eax
            //   e8????????           |                     

        $sequence_8 = { 488d1d89520100 488b0b ff15???????? ffc7 488903 4863c7 488d5b08 }
            // n = 7, score = 100
            //   488d1d89520100       | lea                 ecx, [ebp - 0x78]
            //   488b0b               | dec                 eax
            //   ff15????????         |                     
            //   ffc7                 | lea                 ecx, [ebp + 0x10]
            //   488903               | dec                 eax
            //   4863c7               | cmp                 dword ptr [ebp + 0x28], 0x10
            //   488d5b08             | dec                 esp

        $sequence_9 = { 8a45d8 4b8b8cea00670300 88440e09 8a45d9 }
            // n = 4, score = 100
            //   8a45d8               | nop                 
            //   4b8b8cea00670300     | dec                 eax
            //   88440e09             | lea                 edx, [ebp - 0x50]
            //   8a45d9               | dec                 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*))
}