rule win_crypt0l0cker_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.crypt0l0cker."
        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.crypt0l0cker"
        malpedia_rule_date = "20260422"
        malpedia_hash = "a182e35da64e6d71cb55f125c4d4225196523f14"
        malpedia_version = "20260504"
        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 = { 7447 8802 42 8b048d0028a900 4e 807d1301 6a02 }
            // n = 7, score = 100
            //   7447                 | je                  0x49
            //   8802                 | mov                 byte ptr [edx], al
            //   42                   | inc                 edx
            //   8b048d0028a900       | mov                 eax, dword ptr [ecx*4 + 0xa92800]
            //   4e                   | dec                 esi
            //   807d1301             | cmp                 byte ptr [ebp + 0x13], 1
            //   6a02                 | push                2

        $sequence_1 = { 3bc1 7717 50 8b45f4 ff75f8 03c6 50 }
            // n = 7, score = 100
            //   3bc1                 | cmp                 eax, ecx
            //   7717                 | ja                  0x19
            //   50                   | push                eax
            //   8b45f4               | mov                 eax, dword ptr [ebp - 0xc]
            //   ff75f8               | push                dword ptr [ebp - 8]
            //   03c6                 | add                 eax, esi
            //   50                   | push                eax

        $sequence_2 = { e8???????? 83c404 85c0 0f8576010000 68???????? ba57a597ab 8bce }
            // n = 7, score = 100
            //   e8????????           |                     
            //   83c404               | add                 esp, 4
            //   85c0                 | test                eax, eax
            //   0f8576010000         | jne                 0x17c
            //   68????????           |                     
            //   ba57a597ab           | mov                 edx, 0xab97a557
            //   8bce                 | mov                 ecx, esi

        $sequence_3 = { 49 898d2cfdffff 85c0 0f84cc040000 8b8530fdffff ffb524fdffff 40 }
            // n = 7, score = 100
            //   49                   | dec                 ecx
            //   898d2cfdffff         | mov                 dword ptr [ebp - 0x2d4], ecx
            //   85c0                 | test                eax, eax
            //   0f84cc040000         | je                  0x4d2
            //   8b8530fdffff         | mov                 eax, dword ptr [ebp - 0x2d0]
            //   ffb524fdffff         | push                dword ptr [ebp - 0x2dc]
            //   40                   | inc                 eax

        $sequence_4 = { 8bc8 894dec 85c9 0f8433010000 8b45f8 3bf8 7f61 }
            // n = 7, score = 100
            //   8bc8                 | mov                 ecx, eax
            //   894dec               | mov                 dword ptr [ebp - 0x14], ecx
            //   85c9                 | test                ecx, ecx
            //   0f8433010000         | je                  0x139
            //   8b45f8               | mov                 eax, dword ptr [ebp - 8]
            //   3bf8                 | cmp                 edi, eax
            //   7f61                 | jg                  0x63

        $sequence_5 = { 833e00 75f6 6a24 e8???????? 83c404 8906 85c0 }
            // n = 7, score = 100
            //   833e00               | cmp                 dword ptr [esi], 0
            //   75f6                 | jne                 0xfffffff8
            //   6a24                 | push                0x24
            //   e8????????           |                     
            //   83c404               | add                 esp, 4
            //   8906                 | mov                 dword ptr [esi], eax
            //   85c0                 | test                eax, eax

        $sequence_6 = { 52 8b55fc a5 50 }
            // n = 4, score = 100
            //   52                   | push                edx
            //   8b55fc               | mov                 edx, dword ptr [ebp - 4]
            //   a5                   | movsd               dword ptr es:[edi], dword ptr [esi]
            //   50                   | push                eax

        $sequence_7 = { c1e210 c1e810 03fa 03c8 897de8 }
            // n = 5, score = 100
            //   c1e210               | shl                 edx, 0x10
            //   c1e810               | shr                 eax, 0x10
            //   03fa                 | add                 edi, edx
            //   03c8                 | add                 ecx, eax
            //   897de8               | mov                 dword ptr [ebp - 0x18], edi

        $sequence_8 = { 50 8d542420 e8???????? 83c408 85c0 0f84ce000000 }
            // n = 6, score = 100
            //   50                   | push                eax
            //   8d542420             | lea                 edx, [esp + 0x20]
            //   e8????????           |                     
            //   83c408               | add                 esp, 8
            //   85c0                 | test                eax, eax
            //   0f84ce000000         | je                  0xd4

        $sequence_9 = { 57 e8???????? 83c40c 56 8b75f8 57 8d4610 }
            // n = 7, score = 100
            //   57                   | push                edi
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc
            //   56                   | push                esi
            //   8b75f8               | mov                 esi, dword ptr [ebp - 8]
            //   57                   | push                edi
            //   8d4610               | lea                 eax, [esi + 0x10]

    condition:
        7 of them and filesize < 917504
}