rule win_dircrypt_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.dircrypt."
        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.dircrypt"
        malpedia_rule_date = "20260916"
        malpedia_hash = "53a643781c18e08f4a50949af60172d837a0b6f6"
        malpedia_version = "20260917"
        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 = { c705????????01000000 e8???????? e8???????? e8???????? 833d????????00 7514 68???????? }
            // n = 7, score = 900
            //   c705????????01000000     |     
            //   e8????????           |                     
            //   e8????????           |                     
            //   e8????????           |                     
            //   833d????????00       |                     
            //   7514                 | jne                 0x16
            //   68????????           |                     

        $sequence_1 = { ff15???????? 8945fc 8b450c 2b4508 50 }
            // n = 5, score = 900
            //   ff15????????         |                     
            //   8945fc               | mov                 dword ptr [ebp - 4], eax
            //   8b450c               | mov                 eax, dword ptr [ebp + 0xc]
            //   2b4508               | sub                 eax, dword ptr [ebp + 8]
            //   50                   | push                eax

        $sequence_2 = { 6a00 68???????? e8???????? 68f4010000 ff15???????? }
            // n = 5, score = 900
            //   6a00                 | push                0
            //   68????????           |                     
            //   e8????????           |                     
            //   68f4010000           | push                0x1f4
            //   ff15????????         |                     

        $sequence_3 = { 6a00 6a00 8d45fc 50 68???????? 6802000080 }
            // n = 6, score = 900
            //   6a00                 | push                0
            //   6a00                 | push                0
            //   8d45fc               | lea                 eax, [ebp - 4]
            //   50                   | push                eax
            //   68????????           |                     
            //   6802000080           | push                0x80000002

        $sequence_4 = { 51 ff15???????? 8945fc 8b450c 2b4508 50 }
            // n = 6, score = 900
            //   51                   | push                ecx
            //   ff15????????         |                     
            //   8945fc               | mov                 dword ptr [ebp - 4], eax
            //   8b450c               | mov                 eax, dword ptr [ebp + 0xc]
            //   2b4508               | sub                 eax, dword ptr [ebp + 8]
            //   50                   | push                eax

        $sequence_5 = { c705????????01000000 e8???????? e8???????? 833d????????00 7514 }
            // n = 5, score = 900
            //   c705????????01000000     |     
            //   e8????????           |                     
            //   e8????????           |                     
            //   833d????????00       |                     
            //   7514                 | jne                 0x16

        $sequence_6 = { 6a00 8d45fc 50 68???????? 6802000080 }
            // n = 5, score = 900
            //   6a00                 | push                0
            //   8d45fc               | lea                 eax, [ebp - 4]
            //   50                   | push                eax
            //   68????????           |                     
            //   6802000080           | push                0x80000002

        $sequence_7 = { f7d8 1bc0 83e0e0 83c061 }
            // n = 4, score = 900
            //   f7d8                 | neg                 eax
            //   1bc0                 | sbb                 eax, eax
            //   83e0e0               | and                 eax, 0xffffffe0
            //   83c061               | add                 eax, 0x61

        $sequence_8 = { 6a00 8d45fc 50 68???????? 6802000080 e8???????? 85c0 }
            // n = 7, score = 900
            //   6a00                 | push                0
            //   8d45fc               | lea                 eax, [ebp - 4]
            //   50                   | push                eax
            //   68????????           |                     
            //   6802000080           | push                0x80000002
            //   e8????????           |                     
            //   85c0                 | test                eax, eax

        $sequence_9 = { e8???????? 05d5070000 50 6a01 6a02 6a08 }
            // n = 6, score = 900
            //   e8????????           |                     
            //   05d5070000           | add                 eax, 0x7d5
            //   50                   | push                eax
            //   6a01                 | push                1
            //   6a02                 | push                2
            //   6a08                 | push                8

    condition:
        7 of them and filesize < 671744
}