rule win_regretlocker_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.regretlocker."
        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.regretlocker"
        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 = { 57 68???????? e8???????? 68???????? e8???????? 83c40c eb12 }
            // n = 7, score = 100
            //   57                   | push                edi
            //   68????????           |                     
            //   e8????????           |                     
            //   68????????           |                     
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc
            //   eb12                 | jmp                 0x14

        $sequence_1 = { 8bf1 8975ec 8945f0 39450c 741e c706???????? c74610400d4500 }
            // n = 7, score = 100
            //   8bf1                 | mov                 esi, ecx
            //   8975ec               | mov                 dword ptr [ebp - 0x14], esi
            //   8945f0               | mov                 dword ptr [ebp - 0x10], eax
            //   39450c               | cmp                 dword ptr [ebp + 0xc], eax
            //   741e                 | je                  0x20
            //   c706????????         |                     
            //   c74610400d4500       | mov                 dword ptr [esi + 0x10], 0x450d40

        $sequence_2 = { 68???????? 50 e8???????? 59 59 8d8decfdffff e8???????? }
            // n = 7, score = 100
            //   68????????           |                     
            //   50                   | push                eax
            //   e8????????           |                     
            //   59                   | pop                 ecx
            //   59                   | pop                 ecx
            //   8d8decfdffff         | lea                 ecx, [ebp - 0x214]
            //   e8????????           |                     

        $sequence_3 = { 3de8030000 0f84fa000000 83f803 0f84f1000000 83ffff 0f84e8000000 8d45c4 }
            // n = 7, score = 100
            //   3de8030000           | cmp                 eax, 0x3e8
            //   0f84fa000000         | je                  0x100
            //   83f803               | cmp                 eax, 3
            //   0f84f1000000         | je                  0xf7
            //   83ffff               | cmp                 edi, -1
            //   0f84e8000000         | je                  0xee
            //   8d45c4               | lea                 eax, [ebp - 0x3c]

        $sequence_4 = { 8b450c 33d2 53 56 57 6a3c 5f }
            // n = 7, score = 100
            //   8b450c               | mov                 eax, dword ptr [ebp + 0xc]
            //   33d2                 | xor                 edx, edx
            //   53                   | push                ebx
            //   56                   | push                esi
            //   57                   | push                edi
            //   6a3c                 | push                0x3c
            //   5f                   | pop                 edi

        $sequence_5 = { 81ec94010000 56 57 8bf1 68???????? 89b528ffffff e8???????? }
            // n = 7, score = 100
            //   81ec94010000         | sub                 esp, 0x194
            //   56                   | push                esi
            //   57                   | push                edi
            //   8bf1                 | mov                 esi, ecx
            //   68????????           |                     
            //   89b528ffffff         | mov                 dword ptr [ebp - 0xd8], esi
            //   e8????????           |                     

        $sequence_6 = { 2bc8 394de8 8bc1 0f4645e8 3bf9 8945e8 8bc1 }
            // n = 7, score = 100
            //   2bc8                 | sub                 ecx, eax
            //   394de8               | cmp                 dword ptr [ebp - 0x18], ecx
            //   8bc1                 | mov                 eax, ecx
            //   0f4645e8             | cmovbe              eax, dword ptr [ebp - 0x18]
            //   3bf9                 | cmp                 edi, ecx
            //   8945e8               | mov                 dword ptr [ebp - 0x18], eax
            //   8bc1                 | mov                 eax, ecx

        $sequence_7 = { c645fc0e e8???????? 33c9 884d9c ff759c 898d24ffffff 898d28ffffff }
            // n = 7, score = 100
            //   c645fc0e             | mov                 byte ptr [ebp - 4], 0xe
            //   e8????????           |                     
            //   33c9                 | xor                 ecx, ecx
            //   884d9c               | mov                 byte ptr [ebp - 0x64], cl
            //   ff759c               | push                dword ptr [ebp - 0x64]
            //   898d24ffffff         | mov                 dword ptr [ebp - 0xdc], ecx
            //   898d28ffffff         | mov                 dword ptr [ebp - 0xd8], ecx

        $sequence_8 = { 8b75dc 0f4345cc 8b4dec 2bf1 03f0 85f6 7e19 }
            // n = 7, score = 100
            //   8b75dc               | mov                 esi, dword ptr [ebp - 0x24]
            //   0f4345cc             | cmovae              eax, dword ptr [ebp - 0x34]
            //   8b4dec               | mov                 ecx, dword ptr [ebp - 0x14]
            //   2bf1                 | sub                 esi, ecx
            //   03f0                 | add                 esi, eax
            //   85f6                 | test                esi, esi
            //   7e19                 | jle                 0x1b

        $sequence_9 = { 894110 894114 e8???????? 8b4df4 8bc6 5e 64890d00000000 }
            // n = 7, score = 100
            //   894110               | mov                 dword ptr [ecx + 0x10], eax
            //   894114               | mov                 dword ptr [ecx + 0x14], eax
            //   e8????????           |                     
            //   8b4df4               | mov                 ecx, dword ptr [ebp - 0xc]
            //   8bc6                 | mov                 eax, esi
            //   5e                   | pop                 esi
            //   64890d00000000       | mov                 dword ptr fs:[0], ecx

    condition:
        7 of them and filesize < 1021952
}