rule win_ragnarlocker_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.ragnarlocker."
        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.ragnarlocker"
        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 = { 8b7d90 13d6 014de8 8bf7 8bcf 13d3 33db }
            // n = 7, score = 300
            //   8b7d90               | mov                 edi, dword ptr [ebp - 0x70]
            //   13d6                 | adc                 edx, esi
            //   014de8               | add                 dword ptr [ebp - 0x18], ecx
            //   8bf7                 | mov                 esi, edi
            //   8bcf                 | mov                 ecx, edi
            //   13d3                 | adc                 edx, ebx
            //   33db                 | xor                 ebx, ebx

        $sequence_1 = { b82c000000 668945f4 8d45f4 50 56 e8???????? 83c408 }
            // n = 7, score = 300
            //   b82c000000           | mov                 eax, 0x2c
            //   668945f4             | mov                 word ptr [ebp - 0xc], ax
            //   8d45f4               | lea                 eax, [ebp - 0xc]
            //   50                   | push                eax
            //   56                   | push                esi
            //   e8????????           |                     
            //   83c408               | add                 esp, 8

        $sequence_2 = { 3175fc 8b4db4 8bf1 3375f8 234df8 8b55f0 }
            // n = 6, score = 300
            //   3175fc               | xor                 dword ptr [ebp - 4], esi
            //   8b4db4               | mov                 ecx, dword ptr [ebp - 0x4c]
            //   8bf1                 | mov                 esi, ecx
            //   3375f8               | xor                 esi, dword ptr [ebp - 8]
            //   234df8               | and                 ecx, dword ptr [ebp - 8]
            //   8b55f0               | mov                 edx, dword ptr [ebp - 0x10]

        $sequence_3 = { c1ea08 0bd9 8b8d50ffffff c1e618 0bf2 8b956cffffff }
            // n = 6, score = 300
            //   c1ea08               | shr                 edx, 8
            //   0bd9                 | or                  ebx, ecx
            //   8b8d50ffffff         | mov                 ecx, dword ptr [ebp - 0xb0]
            //   c1e618               | shl                 esi, 0x18
            //   0bf2                 | or                  esi, edx
            //   8b956cffffff         | mov                 edx, dword ptr [ebp - 0x94]

        $sequence_4 = { 8d8560f9ffff 50 ffd6 6a01 8d8560f9ffff 57 50 }
            // n = 7, score = 300
            //   8d8560f9ffff         | lea                 eax, [ebp - 0x6a0]
            //   50                   | push                eax
            //   ffd6                 | call                esi
            //   6a01                 | push                1
            //   8d8560f9ffff         | lea                 eax, [ebp - 0x6a0]
            //   57                   | push                edi
            //   50                   | push                eax

        $sequence_5 = { 3375f4 2375b8 8b4dd4 234df4 8b55c0 }
            // n = 5, score = 300
            //   3375f4               | xor                 esi, dword ptr [ebp - 0xc]
            //   2375b8               | and                 esi, dword ptr [ebp - 0x48]
            //   8b4dd4               | mov                 ecx, dword ptr [ebp - 0x2c]
            //   234df4               | and                 ecx, dword ptr [ebp - 0xc]
            //   8b55c0               | mov                 edx, dword ptr [ebp - 0x40]

        $sequence_6 = { 13fa 039d44ffffff 13bd38ffffff 039d18ffffff 13bd14ffffff 81c32f3b4dec 81d7cffbc0b5 }
            // n = 7, score = 300
            //   13fa                 | adc                 edi, edx
            //   039d44ffffff         | add                 ebx, dword ptr [ebp - 0xbc]
            //   13bd38ffffff         | adc                 edi, dword ptr [ebp - 0xc8]
            //   039d18ffffff         | add                 ebx, dword ptr [ebp - 0xe8]
            //   13bd14ffffff         | adc                 edi, dword ptr [ebp - 0xec]
            //   81c32f3b4dec         | add                 ebx, 0xec4d3b2f
            //   81d7cffbc0b5         | adc                 edi, 0xb5c0fbcf

        $sequence_7 = { 660f1f840000000000 8b7508 8a840d20ffffff ff4508 3206 8b75cc 8807 }
            // n = 7, score = 300
            //   660f1f840000000000     | nop    word ptr [eax + eax]
            //   8b7508               | mov                 esi, dword ptr [ebp + 8]
            //   8a840d20ffffff       | mov                 al, byte ptr [ebp + ecx - 0xe0]
            //   ff4508               | inc                 dword ptr [ebp + 8]
            //   3206                 | xor                 al, byte ptr [esi]
            //   8b75cc               | mov                 esi, dword ptr [ebp - 0x34]
            //   8807                 | mov                 byte ptr [edi], al

        $sequence_8 = { 8b7d08 8bd9 85ff 0f84a1010000 56 8b750c }
            // n = 6, score = 300
            //   8b7d08               | mov                 edi, dword ptr [ebp + 8]
            //   8bd9                 | mov                 ebx, ecx
            //   85ff                 | test                edi, edi
            //   0f84a1010000         | je                  0x1a7
            //   56                   | push                esi
            //   8b750c               | mov                 esi, dword ptr [ebp + 0xc]

        $sequence_9 = { 50 ff32 8b45fc 6a00 6a01 6a00 ff7004 }
            // n = 7, score = 300
            //   50                   | push                eax
            //   ff32                 | push                dword ptr [edx]
            //   8b45fc               | mov                 eax, dword ptr [ebp - 4]
            //   6a00                 | push                0
            //   6a01                 | push                1
            //   6a00                 | push                0
            //   ff7004               | push                dword ptr [eax + 4]

    condition:
        7 of them and filesize < 147456
}