rule win_ransomlock_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.ransomlock."
        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.ransomlock"
        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 = { 746a 81f913010000 741b 8b5514 }
            // n = 4, score = 100
            //   746a                 | je                  0x6c
            //   81f913010000         | cmp                 ecx, 0x113
            //   741b                 | je                  0x1d
            //   8b5514               | mov                 edx, dword ptr [ebp + 0x14]

        $sequence_1 = { 85d2 744e 8b4514 8b08 81f900020000 7241 }
            // n = 6, score = 100
            //   85d2                 | test                edx, edx
            //   744e                 | je                  0x50
            //   8b4514               | mov                 eax, dword ptr [ebp + 0x14]
            //   8b08                 | mov                 ecx, dword ptr [eax]
            //   81f900020000         | cmp                 ecx, 0x200
            //   7241                 | jb                  0x43

        $sequence_2 = { f3a4 52 ff15???????? 8b45f8 8b10 50 }
            // n = 6, score = 100
            //   f3a4                 | rep movsb           byte ptr es:[edi], byte ptr [esi]
            //   52                   | push                edx
            //   ff15????????         |                     
            //   8b45f8               | mov                 eax, dword ptr [ebp - 8]
            //   8b10                 | mov                 edx, dword ptr [eax]
            //   50                   | push                eax

        $sequence_3 = { 8bec 8b5510 8b4508 8b48f4 }
            // n = 4, score = 100
            //   8bec                 | mov                 ebp, esp
            //   8b5510               | mov                 edx, dword ptr [ebp + 0x10]
            //   8b4508               | mov                 eax, dword ptr [ebp + 8]
            //   8b48f4               | mov                 ecx, dword ptr [eax - 0xc]

        $sequence_4 = { 57 8bcb ba???????? c70600000000 e8???????? 8b7d08 85c0 }
            // n = 7, score = 100
            //   57                   | push                edi
            //   8bcb                 | mov                 ecx, ebx
            //   ba????????           |                     
            //   c70600000000         | mov                 dword ptr [esi], 0
            //   e8????????           |                     
            //   8b7d08               | mov                 edi, dword ptr [ebp + 8]
            //   85c0                 | test                eax, eax

        $sequence_5 = { 8bc1 48 7423 48 0f85b2000000 }
            // n = 5, score = 100
            //   8bc1                 | mov                 eax, ecx
            //   48                   | dec                 eax
            //   7423                 | je                  0x25
            //   48                   | dec                 eax
            //   0f85b2000000         | jne                 0xb8

        $sequence_6 = { 8b483c 0fb7540114 03c8 0fb74106 03d1 8d0480 }
            // n = 6, score = 100
            //   8b483c               | mov                 ecx, dword ptr [eax + 0x3c]
            //   0fb7540114           | movzx               edx, word ptr [ecx + eax + 0x14]
            //   03c8                 | add                 ecx, eax
            //   0fb74106             | movzx               eax, word ptr [ecx + 6]
            //   03d1                 | add                 edx, ecx
            //   8d0480               | lea                 eax, [eax + eax*4]

        $sequence_7 = { 74b6 eb04 3bc3 7408 8b08 8b5108 50 }
            // n = 7, score = 100
            //   74b6                 | je                  0xffffffb8
            //   eb04                 | jmp                 6
            //   3bc3                 | cmp                 eax, ebx
            //   7408                 | je                  0xa
            //   8b08                 | mov                 ecx, dword ptr [eax]
            //   8b5108               | mov                 edx, dword ptr [ecx + 8]
            //   50                   | push                eax

        $sequence_8 = { 8b3f 85ff 7411 8b0f 8b5104 }
            // n = 5, score = 100
            //   8b3f                 | mov                 edi, dword ptr [edi]
            //   85ff                 | test                edi, edi
            //   7411                 | je                  0x13
            //   8b0f                 | mov                 ecx, dword ptr [edi]
            //   8b5104               | mov                 edx, dword ptr [ecx + 4]

        $sequence_9 = { 8b45e0 2b55d4 2b45d8 8b35???????? 68???????? }
            // n = 5, score = 100
            //   8b45e0               | mov                 eax, dword ptr [ebp - 0x20]
            //   2b55d4               | sub                 edx, dword ptr [ebp - 0x2c]
            //   2b45d8               | sub                 eax, dword ptr [ebp - 0x28]
            //   8b35????????         |                     
            //   68????????           |                     

    condition:
        7 of them and filesize < 360448
}