rule win_badflick_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.badflick"
        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 = { 50 6a00 6a01 53 e8???????? 83c410 8d45e0 }
            // n = 7, score = 100
            //   50                   | push                eax
            //   6a00                 | push                0
            //   6a01                 | push                1
            //   53                   | push                ebx
            //   e8????????           |                     
            //   83c410               | add                 esp, 0x10
            //   8d45e0               | lea                 eax, [ebp - 0x20]

        $sequence_1 = { ff35???????? ff750c ff75fc ff33 e8???????? 8b7d10 83c418 }
            // n = 7, score = 100
            //   ff35????????         |                     
            //   ff750c               | push                dword ptr [ebp + 0xc]
            //   ff75fc               | push                dword ptr [ebp - 4]
            //   ff33                 | push                dword ptr [ebx]
            //   e8????????           |                     
            //   8b7d10               | mov                 edi, dword ptr [ebp + 0x10]
            //   83c418               | add                 esp, 0x18

        $sequence_2 = { 85c0 7471 8b07 3b45fc 756a 0fb74606 }
            // n = 6, score = 100
            //   85c0                 | test                eax, eax
            //   7471                 | je                  0x73
            //   8b07                 | mov                 eax, dword ptr [edi]
            //   3b45fc               | cmp                 eax, dword ptr [ebp - 4]
            //   756a                 | jne                 0x6c
            //   0fb74606             | movzx               eax, word ptr [esi + 6]

        $sequence_3 = { ff15???????? 8bd8 83fbff 746b 56 }
            // n = 5, score = 100
            //   ff15????????         |                     
            //   8bd8                 | mov                 ebx, eax
            //   83fbff               | cmp                 ebx, -1
            //   746b                 | je                  0x6d
            //   56                   | push                esi

        $sequence_4 = { 8d45f8 50 56 ff75f0 ff75f4 ff15???????? 85c0 }
            // n = 7, score = 100
            //   8d45f8               | lea                 eax, [ebp - 8]
            //   50                   | push                eax
            //   56                   | push                esi
            //   ff75f0               | push                dword ptr [ebp - 0x10]
            //   ff75f4               | push                dword ptr [ebp - 0xc]
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax

        $sequence_5 = { 8d7dd8 f3ab 8d85a8fbffff 50 }
            // n = 4, score = 100
            //   8d7dd8               | lea                 edi, [ebp - 0x28]
            //   f3ab                 | rep stosd           dword ptr es:[edi], eax
            //   8d85a8fbffff         | lea                 eax, [ebp - 0x458]
            //   50                   | push                eax

        $sequence_6 = { 68???????? ff15???????? 83c40c e9???????? e8???????? }
            // n = 5, score = 100
            //   68????????           |                     
            //   ff15????????         |                     
            //   83c40c               | add                 esp, 0xc
            //   e9????????           |                     
            //   e8????????           |                     

        $sequence_7 = { c3 df6df8 51 dd05???????? 51 dcc9 dec9 }
            // n = 7, score = 100
            //   c3                   | ret                 
            //   df6df8               | fild                qword ptr [ebp - 8]
            //   51                   | push                ecx
            //   dd05????????         |                     
            //   51                   | push                ecx
            //   dcc9                 | fmul                st(1), st(0)
            //   dec9                 | fmulp               st(1)

        $sequence_8 = { 8b431d 8d444321 50 ffd6 6a20 8945ec e8???????? }
            // n = 7, score = 100
            //   8b431d               | mov                 eax, dword ptr [ebx + 0x1d]
            //   8d444321             | lea                 eax, [ebx + eax*2 + 0x21]
            //   50                   | push                eax
            //   ffd6                 | call                esi
            //   6a20                 | push                0x20
            //   8945ec               | mov                 dword ptr [ebp - 0x14], eax
            //   e8????????           |                     

        $sequence_9 = { 6a01 ff7305 e8???????? 59 50 56 e8???????? }
            // n = 7, score = 100
            //   6a01                 | push                1
            //   ff7305               | push                dword ptr [ebx + 5]
            //   e8????????           |                     
            //   59                   | pop                 ecx
            //   50                   | push                eax
            //   56                   | push                esi
            //   e8????????           |                     

    condition:
        7 of them and filesize < 81920
}

rule win_badflick_w0 {
    meta:
		description = "Detects BADFLICK backdoor"
		author = "@VK_Intel"
		reference = "BADFLICK backdoor"
		date = "2018-03-26"
		hash = "7ba05abdf8f0323aa30c3d52e22df951eb5b67a2620014336eab7907b0a5cedf"
		reference = "https://www.fireeye.com/blog/threat-research/2018/03/suspected-chinese-espionage-group-targeting-maritime-and-engineering-industries.html"
		malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.badflick"
		malpedia_version = "20180407"
		malpedia_license = "CC BY-NC-SA 4.0"
		malpedia_sharing = "TLP:WHITE"
    strings:
		$s0 = "%s\\en-US\\cmd.exe.mui" fullword wide
		$s1 = "[Green] pid=%d tid=%d modulePath=%s|" fullword wide
		$s2 = "1|103.243.175.181|80|5|xxxxxxxxxxxxxxxxxxxxxxx" wide ascii
		$s3 = "modulePath=%[^|]" fullword wide
		$s4 = "%s:%d:%s:%d:%d" fullword ascii
		$s5 = "regsvr32 %s %s %s go \"%s\"" fullword wide
		$s6 = "modulePath=" fullword wide
		$s7 = "%d %d.%d.%d %s" fullword wide
		$s8 = "winMain static green" fullword wide
		$s9 = "o%d Core %.2f GHz" fullword wide
		$s10 = "6&62676=6B6G6N6c6s6" fullword ascii

		$op0 = { 8b 54 24 54 8b cf 2b cb 8d 04 0a 3b c7 76 02 8b } 
		$op1 = { a1 08 77 40 00 89 45 94 8d 45 94 50 ff 35 04 77 } 
		$op2 = { 8b 7c 24 14 8b f7 2b f5 8d 64 24 00 8a 1f 84 db }
	condition:
		uint16(0) == 0x5a4d and filesize < 108KB and 8 of ($s*) and 1 of ($op*)
}