rule win_chainshot_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2022-08-05"
        version = "1"
        description = "Detects win.chainshot."
        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.chainshot"
        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 = { 0f844e0e0000 ffc8 0f84d8110000 ffc8 }
            // n = 4, score = 300
            //   0f844e0e0000         | dec                 ebp
            //   ffc8                 | je                  0x2cf
            //   0f84d8110000         | test                edx, edx
            //   ffc8                 | je                  0x2cf

        $sequence_1 = { bd01000000 c70703000000 ebe9 bd01000000 c7070b000000 }
            // n = 5, score = 300
            //   bd01000000           | inc                 ecx
            //   c70703000000         | cmp                 edi, edi
            //   ebe9                 | mov                 dword ptr [esp + 0x20], esp
            //   bd01000000           | int3                
            //   c7070b000000         | dec                 eax

        $sequence_2 = { 7708 7519 66892c5f eb13 66892c5f be7a000780 eb08 }
            // n = 7, score = 300
            //   7708                 | test                eax, eax
            //   7519                 | je                  0x207
            //   66892c5f             | call                eax
            //   eb13                 | mov                 ecx, 0x80000043
            //   66892c5f             | jmp                 0x27c
            //   be7a000780           | dec                 eax
            //   eb08                 | test                eax, eax

        $sequence_3 = { 754a c705????????05000000 eb67 83fa05 7539 }
            // n = 5, score = 300
            //   754a                 | dec                 eax
            //   c705????????05000000     |     
            //   eb67                 | mov                 edx, dword ptr [esp + 0x80]
            //   83fa05               | dec                 eax
            //   7539                 | dec                 esp

        $sequence_4 = { 84db 7507 b929080080 eb19 }
            // n = 4, score = 300
            //   84db                 | dec                 eax
            //   7507                 | jne                 0x115
            //   b929080080           | mov                 ebx, 0x80000005
            //   eb19                 | jne                 0x11c

        $sequence_5 = { 85c0 7407 b908000080 eb21 }
            // n = 4, score = 300
            //   85c0                 | jne                 0x30
            //   7407                 | inc                 ecx
            //   b908000080           | cmp                 al, dl
            //   eb21                 | jne                 0xdf

        $sequence_6 = { ffc8 0f84d8110000 ffc8 0f8423110000 ffc8 }
            // n = 5, score = 300
            //   ffc8                 | mov                 ecx, esi
            //   0f84d8110000         | lea                 edx, [ebp - 0x30]
            //   ffc8                 | inc                 ebp
            //   0f8423110000         | lea                 eax, [ecx + 0x2c]
            //   ffc8                 | dec                 eax

        $sequence_7 = { e8???????? 85c0 0f8891000000 8b0f 85c9 7503 8b4f10 }
            // n = 7, score = 300
            //   e8????????           |                     
            //   85c0                 | mov                 dword ptr [esp + 0x40], ecx
            //   0f8891000000         | mov                 byte ptr [ecx], al
            //   8b0f                 | dec                 ecx
            //   85c9                 | inc                 ecx
            //   7503                 | dec                 eax
            //   8b4f10               | dec                 ecx

        $sequence_8 = { b902070080 ebd9 ff15???????? 3db7000000 750a }
            // n = 5, score = 300
            //   b902070080           | dec                 ecx
            //   ebd9                 | mov                 edx, esp
            //   ff15????????         |                     
            //   3db7000000           | jmp                 0x11f
            //   750a                 | dec                 eax

        $sequence_9 = { 8ad8 84c0 7507 b901080080 ebde }
            // n = 5, score = 300
            //   8ad8                 | jmp                 0x75
            //   84c0                 | mov                 ecx, 0x201
            //   7507                 | jne                 0xc6
            //   b901080080           | mov                 ecx, 0x80000801
            //   ebde                 | jmp                 0x113

    condition:
        7 of them and filesize < 802816
}