rule win_bart_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2022-11-21"
        version = "1"
        description = "Detects win.bart."
        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.bart"
        malpedia_rule_date = "20221118"
        malpedia_hash = "e0702e2e6d1d00da65c8a29a4ebacd0a4c59e1af"
        malpedia_version = "20221125"
        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 ff15???????? 6a07 53 8d55e0 8d4d84 }
            // n = 6, score = 100
            //   50                   | push                eax
            //   ff15????????         |                     
            //   6a07                 | push                7
            //   53                   | push                ebx
            //   8d55e0               | lea                 edx, [ebp - 0x20]
            //   8d4d84               | lea                 ecx, [ebp - 0x7c]

        $sequence_1 = { e8???????? ff75c0 fec8 88443dec ffd3 8365c000 }
            // n = 6, score = 100
            //   e8????????           |                     
            //   ff75c0               | push                dword ptr [ebp - 0x40]
            //   fec8                 | dec                 al
            //   88443dec             | mov                 byte ptr [ebp + edi - 0x14], al
            //   ffd3                 | call                ebx
            //   8365c000             | and                 dword ptr [ebp - 0x40], 0

        $sequence_2 = { 095e1c eb1e 8d5620 3bd6 7617 }
            // n = 5, score = 100
            //   095e1c               | or                  dword ptr [esi + 0x1c], ebx
            //   eb1e                 | jmp                 0x20
            //   8d5620               | lea                 edx, [esi + 0x20]
            //   3bd6                 | cmp                 edx, esi
            //   7617                 | jbe                 0x19

        $sequence_3 = { 8a06 50 53 897594 c745dc03000000 f30f7f45e0 c745f800000000 }
            // n = 7, score = 100
            //   8a06                 | mov                 al, byte ptr [esi]
            //   50                   | push                eax
            //   53                   | push                ebx
            //   897594               | mov                 dword ptr [ebp - 0x6c], esi
            //   c745dc03000000       | mov                 dword ptr [ebp - 0x24], 3
            //   f30f7f45e0           | movdqu              xmmword ptr [ebp - 0x20], xmm0
            //   c745f800000000       | mov                 dword ptr [ebp - 8], 0

        $sequence_4 = { 8b7dec 8b5508 6a0c 5b 8b4204 2b02 99 }
            // n = 7, score = 100
            //   8b7dec               | mov                 edi, dword ptr [ebp - 0x14]
            //   8b5508               | mov                 edx, dword ptr [ebp + 8]
            //   6a0c                 | push                0xc
            //   5b                   | pop                 ebx
            //   8b4204               | mov                 eax, dword ptr [edx + 4]
            //   2b02                 | sub                 eax, dword ptr [edx]
            //   99                   | cdq                 

        $sequence_5 = { 0fb6c2 8d9b00000000 0b31 8d4904 48 75f8 33c0 }
            // n = 7, score = 100
            //   0fb6c2               | movzx               eax, dl
            //   8d9b00000000         | lea                 ebx, [ebx]
            //   0b31                 | or                  esi, dword ptr [ecx]
            //   8d4904               | lea                 ecx, [ecx + 4]
            //   48                   | dec                 eax
            //   75f8                 | jne                 0xfffffffa
            //   33c0                 | xor                 eax, eax

        $sequence_6 = { ff15???????? ff74241c 8d542418 ff74241c 8d4c2418 }
            // n = 5, score = 100
            //   ff15????????         |                     
            //   ff74241c             | push                dword ptr [esp + 0x1c]
            //   8d542418             | lea                 edx, [esp + 0x18]
            //   ff74241c             | push                dword ptr [esp + 0x1c]
            //   8d4c2418             | lea                 ecx, [esp + 0x18]

        $sequence_7 = { 81ffffffff7f 7605 be57000780 85f6 782f 53 8b5d08 }
            // n = 7, score = 100
            //   81ffffffff7f         | cmp                 edi, 0x7fffffff
            //   7605                 | jbe                 7
            //   be57000780           | mov                 esi, 0x80070057
            //   85f6                 | test                esi, esi
            //   782f                 | js                  0x31
            //   53                   | push                ebx
            //   8b5d08               | mov                 ebx, dword ptr [ebp + 8]

        $sequence_8 = { 8d45ff 6a01 50 53 ffd7 8a4604 8845ff }
            // n = 7, score = 100
            //   8d45ff               | lea                 eax, [ebp - 1]
            //   6a01                 | push                1
            //   50                   | push                eax
            //   53                   | push                ebx
            //   ffd7                 | call                edi
            //   8a4604               | mov                 al, byte ptr [esi + 4]
            //   8845ff               | mov                 byte ptr [ebp - 1], al

        $sequence_9 = { 53 0fb7c0 663bc1 7504 8bd9 }
            // n = 5, score = 100
            //   53                   | push                ebx
            //   0fb7c0               | movzx               eax, ax
            //   663bc1               | cmp                 ax, cx
            //   7504                 | jne                 6
            //   8bd9                 | mov                 ebx, ecx

    condition:
        7 of them and filesize < 163840
}