rule win_pwndlocker_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2023-03-28"
        version = "1"
        description = "Detects win.pwndlocker."
        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.pwndlocker"
        malpedia_rule_date = "20230328"
        malpedia_hash = "9d2d75cef573c1c2d861f5197df8f563b05a305d"
        malpedia_version = "20230407"
        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 = { 8b5620 01da 56 e334 49 8d348a }
            // n = 6, score = 300
            //   8b5620               | mov                 edx, dword ptr [esi + 0x20]
            //   01da                 | add                 edx, ebx
            //   56                   | push                esi
            //   e334                 | jecxz               0x36
            //   49                   | dec                 ecx
            //   8d348a               | lea                 esi, [edx + ecx*4]

        $sequence_1 = { 01d8 83c078 8b00 8d3403 8b4e18 }
            // n = 5, score = 300
            //   01d8                 | add                 eax, ebx
            //   83c078               | add                 eax, 0x78
            //   8b00                 | mov                 eax, dword ptr [eax]
            //   8d3403               | lea                 esi, [ebx + eax]
            //   8b4e18               | mov                 ecx, dword ptr [esi + 0x18]

        $sequence_2 = { ebf4 3b7df0 75e0 5a 8b7224 01de }
            // n = 6, score = 300
            //   ebf4                 | jmp                 0xfffffff6
            //   3b7df0               | cmp                 edi, dword ptr [ebp - 0x10]
            //   75e0                 | jne                 0xffffffe2
            //   5a                   | pop                 edx
            //   8b7224               | mov                 esi, dword ptr [edx + 0x24]
            //   01de                 | add                 esi, ebx

        $sequence_3 = { 84c0 7407 c1cf0d 01c7 }
            // n = 4, score = 300
            //   84c0                 | test                al, al
            //   7407                 | je                  9
            //   c1cf0d               | ror                 edi, 0xd
            //   01c7                 | add                 edi, eax

        $sequence_4 = { 31ff 31c0 fc ac 84c0 7407 }
            // n = 6, score = 300
            //   31ff                 | xor                 edi, edi
            //   31c0                 | xor                 eax, eax
            //   fc                   | cld                 
            //   ac                   | lodsb               al, byte ptr [esi]
            //   84c0                 | test                al, al
            //   7407                 | je                  9

        $sequence_5 = { 75e0 5a 8b7224 01de 31c0 }
            // n = 5, score = 300
            //   75e0                 | jne                 0xffffffe2
            //   5a                   | pop                 edx
            //   8b7224               | mov                 esi, dword ptr [edx + 0x24]
            //   01de                 | add                 esi, ebx
            //   31c0                 | xor                 eax, eax

        $sequence_6 = { c1cf0d 01c7 ebf4 3b7df0 75e0 5a 8b7224 }
            // n = 7, score = 300
            //   c1cf0d               | ror                 edi, 0xd
            //   01c7                 | add                 edi, eax
            //   ebf4                 | jmp                 0xfffffff6
            //   3b7df0               | cmp                 edi, dword ptr [ebp - 0x10]
            //   75e0                 | jne                 0xffffffe2
            //   5a                   | pop                 edx
            //   8b7224               | mov                 esi, dword ptr [edx + 0x24]

        $sequence_7 = { 56 e334 49 8d348a 8b36 }
            // n = 5, score = 300
            //   56                   | push                esi
            //   e334                 | jecxz               0x36
            //   49                   | dec                 ecx
            //   8d348a               | lea                 esi, [edx + ecx*4]
            //   8b36                 | mov                 esi, dword ptr [esi]

        $sequence_8 = { 84c0 7407 c1cf0d 01c7 ebf4 3b7df0 75e0 }
            // n = 7, score = 300
            //   84c0                 | test                al, al
            //   7407                 | je                  9
            //   c1cf0d               | ror                 edi, 0xd
            //   01c7                 | add                 edi, eax
            //   ebf4                 | jmp                 0xfffffff6
            //   3b7df0               | cmp                 edi, dword ptr [ebp - 0x10]
            //   75e0                 | jne                 0xffffffe2

        $sequence_9 = { 8b36 01de 31ff 31c0 fc ac }
            // n = 6, score = 300
            //   8b36                 | mov                 esi, dword ptr [esi]
            //   01de                 | add                 esi, ebx
            //   31ff                 | xor                 edi, edi
            //   31c0                 | xor                 eax, eax
            //   fc                   | cld                 
            //   ac                   | lodsb               al, byte ptr [esi]

    condition:
        7 of them and filesize < 65536
}

rule win_pwndlocker_w0 {
	meta:
		author = "Frank Boldewin (@r3c0nst)"
		description = "Detects Prolock malware in encrypted and decrypted mode"
		reference = "https://raw.githubusercontent.com/fboldewin/YARA-rules/master/Prolock.Malware.yar"
		date = "2020-05-17"
		hash = "a6ded68af5a6e5cc8c1adee029347ec72da3b10a439d98f79f4b15801abd7af0"
		hash = "dfbd62a3d1b239601e17a5533e5cef53036647901f3fb72be76d92063e279178"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.pwndlocker"
        malpedia_version = "20200518"
        malpedia_license = "CC BY-NC-SA 4.0"
        malpedia_sharing = "TLP:WHITE"
		
	strings:
		$DecryptionRoutine = {01 C2 31 DB B8 ?? ?? ?? ?? 31 04 1A 81 3C 1A}
		$DecryptedString1 = "support981723721@protonmail.com" nocase ascii
		$DecryptedString2 = "Your files have been encrypted by ProLock Ransomware" nocase ascii
		$DecryptedString3 = "msaoyrayohnp32tcgwcanhjouetb5k54aekgnwg7dcvtgtecpumrxpqd.onion" nocase ascii
		$CryptoCode = {B8 63 51 E1 B7 31 D2 8D BE ?? ?? ?? ?? B9 63 51 E1 B7 81 C1 B9 79 37 9E}
		
	condition:
		((uint16(0) == 0x5A4D) or (uint16(0) == 0x4D42)) and filesize < 100KB and (($DecryptionRoutine) or (1 of ($DecryptedString*) and $CryptoCode))
}