rule win_bhunt_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2023-07-11"
        version = "1"
        description = "Detects win.bhunt."
        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.bhunt"
        malpedia_rule_date = "20230705"
        malpedia_hash = "42d0574f4405bd7d2b154d321d345acb18834a41"
        malpedia_version = "20230715"
        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 = { 1dcd1e66b1 1dcc7bc13d e23c 37 5d c81d949f a4 }
            // n = 7, score = 100
            //   1dcd1e66b1           | sbb                 eax, 0xb1661ecd
            //   1dcc7bc13d           | sbb                 eax, 0x3dc17bcc
            //   e23c                 | loop                0x3e
            //   37                   | aaa                 
            //   5d                   | pop                 ebp
            //   c81d949f             | enter               -0x6be3, -0x61
            //   a4                   | movsb               byte ptr es:[edi], byte ptr [esi]

        $sequence_1 = { a2???????? 9a05fcd0c3ff9b 2f a4 6940287c3c0e30 6448 8c28 }
            // n = 7, score = 100
            //   a2????????           |                     
            //   9a05fcd0c3ff9b       | lcall               0x9bff:0xc3d0fc05
            //   2f                   | das                 
            //   a4                   | movsb               byte ptr es:[edi], byte ptr [esi]
            //   6940287c3c0e30       | imul                eax, dword ptr [eax + 0x28], 0x300e3c7c
            //   6448                 | dec                 eax
            //   8c28                 | mov                 word ptr [eax], gs

        $sequence_2 = { 3bcb 0f8210010000 83f80f 0f8707010000 7209 83f9e0 0f87fc000000 }
            // n = 7, score = 100
            //   3bcb                 | cmp                 ecx, ebx
            //   0f8210010000         | jb                  0x116
            //   83f80f               | cmp                 eax, 0xf
            //   0f8707010000         | ja                  0x10d
            //   7209                 | jb                  0xb
            //   83f9e0               | cmp                 ecx, -0x20
            //   0f87fc000000         | ja                  0x102

        $sequence_3 = { 0f85b4010000 68???????? ebba 8b4510 5f e8???????? }
            // n = 6, score = 100
            //   0f85b4010000         | jne                 0x1ba
            //   68????????           |                     
            //   ebba                 | jmp                 0xffffffbc
            //   8b4510               | mov                 eax, dword ptr [ebp + 0x10]
            //   5f                   | pop                 edi
            //   e8????????           |                     

        $sequence_4 = { ff7508 e8???????? 3bf3 59 59 7d0f 68???????? }
            // n = 7, score = 100
            //   ff7508               | push                dword ptr [ebp + 8]
            //   e8????????           |                     
            //   3bf3                 | cmp                 esi, ebx
            //   59                   | pop                 ecx
            //   59                   | pop                 ecx
            //   7d0f                 | jge                 0x11
            //   68????????           |                     

        $sequence_5 = { f6d5 40 0f9cc7 4d 0fb7ef 5f 41 }
            // n = 7, score = 100
            //   f6d5                 | not                 ch
            //   40                   | inc                 eax
            //   0f9cc7               | setl                bh
            //   4d                   | dec                 ebp
            //   0fb7ef               | movzx               ebp, di
            //   5f                   | pop                 edi
            //   41                   | inc                 ecx

        $sequence_6 = { 85c0 7c0b 8b490c 6bc018 8b0408 eb05 b8???????? }
            // n = 7, score = 100
            //   85c0                 | test                eax, eax
            //   7c0b                 | jl                  0xd
            //   8b490c               | mov                 ecx, dword ptr [ecx + 0xc]
            //   6bc018               | imul                eax, eax, 0x18
            //   8b0408               | mov                 eax, dword ptr [eax + ecx]
            //   eb05                 | jmp                 7
            //   b8????????           |                     

        $sequence_7 = { d4d1 f779f9 4a 350802d56a 1e 085f44 41 }
            // n = 7, score = 100
            //   d4d1                 | aam                 0xd1
            //   f779f9               | idiv                dword ptr [ecx - 7]
            //   4a                   | dec                 edx
            //   350802d56a           | xor                 eax, 0x6ad50208
            //   1e                   | push                ds
            //   085f44               | or                  byte ptr [edi + 0x44], bl
            //   41                   | inc                 ecx

        $sequence_8 = { ff75f4 6a33 53 e8???????? 6afe 68???????? 6a02 }
            // n = 7, score = 100
            //   ff75f4               | push                dword ptr [ebp - 0xc]
            //   6a33                 | push                0x33
            //   53                   | push                ebx
            //   e8????????           |                     
            //   6afe                 | push                -2
            //   68????????           |                     
            //   6a02                 | push                2

        $sequence_9 = { 7e7b eb03 8b458c 3b4590 8b854cffffff 0f83ff000000 8b5594 }
            // n = 7, score = 100
            //   7e7b                 | jle                 0x7d
            //   eb03                 | jmp                 5
            //   8b458c               | mov                 eax, dword ptr [ebp - 0x74]
            //   3b4590               | cmp                 eax, dword ptr [ebp - 0x70]
            //   8b854cffffff         | mov                 eax, dword ptr [ebp - 0xb4]
            //   0f83ff000000         | jae                 0x105
            //   8b5594               | mov                 edx, dword ptr [ebp - 0x6c]

    condition:
        7 of them and filesize < 19161088
}

import "pe"

rule win_bhunt_w0 {
    meta:
        description = "Detects BHunt Malware Infostealer"
        author = "BlackBerry Research & Intelligence Team"
        date = "Jan 28th 2022"
        license = "This Yara rule is provided under the Apache License 2.0 (https://www.apache.org/licenses/LICENSE-2.0) and open to any user or organization, as long as you use it under this license and ensure originator credit in any derivative to The BlackBerry Research & Intelligence Team"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.bhunt"
        malpedia_version = "20220220"
        malpedia_license = "CC BY-NC-SA 4.0"
        malpedia_sharing = "TLP:WHITE"
        malpedia_rule_date = "20220220"
        malpedia_hash = ""
        
    strings:
        // C2
        $s1 = "http://minecraftsquid.hopto.org/ifo.php" wide
        // Name of assembly in metadata
        $s2 = "BHUNT" wide
        // Outlook misspelled in reg key
        $s3 = "Outllook" wide

    condition:
        // MZ Header
        uint16(0) == 0x5a4d and
        // is a .NET binary
        pe.data_directories[pe.IMAGE_DIRECTORY_ENTRY_COM_DESCRIPTOR].size != 0 and
        all of ($s*)
}