rule win_virlock_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.virlock."
        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.virlock"
        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 = { e8???????? e8???????? ff15???????? 61 3bcb 7532 60 }
            // n = 7, score = 100
            //   e8????????           |                     
            //   e8????????           |                     
            //   ff15????????         |                     
            //   61                   | popal               
            //   3bcb                 | cmp                 ecx, ebx
            //   7532                 | jne                 0x34
            //   60                   | pushal              

        $sequence_1 = { ae a3???????? 1c30 bb47a1ffff 90 90 }
            // n = 6, score = 100
            //   ae                   | scasb               al, byte ptr es:[edi]
            //   a3????????           |                     
            //   1c30                 | sbb                 al, 0x30
            //   bb47a1ffff           | mov                 ebx, 0xffffa147
            //   90                   | nop                 
            //   90                   | nop                 

        $sequence_2 = { 44 48 4e 47 50 4d }
            // n = 6, score = 100
            //   44                   | inc                 esp
            //   48                   | dec                 eax
            //   4e                   | dec                 esi
            //   47                   | inc                 edi
            //   50                   | push                eax
            //   4d                   | dec                 ebp

        $sequence_3 = { 81f29f67d5fa bbf5062af7 baaa94fffe 81f32aa06af9 3dc03d6c09 }
            // n = 5, score = 100
            //   81f29f67d5fa         | xor                 edx, 0xfad5679f
            //   bbf5062af7           | mov                 ebx, 0xf72a06f5
            //   baaa94fffe           | mov                 edx, 0xfeff94aa
            //   81f32aa06af9         | xor                 ebx, 0xf96aa02a
            //   3dc03d6c09           | cmp                 eax, 0x96c3dc0

        $sequence_4 = { 56 42 54 4b 45 55 }
            // n = 6, score = 100
            //   56                   | push                esi
            //   42                   | inc                 edx
            //   54                   | push                esp
            //   4b                   | dec                 ebx
            //   45                   | inc                 ebp
            //   55                   | push                ebp

        $sequence_5 = { 1a2b 25dcd984e8 2331 c1cf51 647bda a0???????? 143b }
            // n = 7, score = 100
            //   1a2b                 | sbb                 ch, byte ptr [ebx]
            //   25dcd984e8           | and                 eax, 0xe884d9dc
            //   2331                 | and                 esi, dword ptr [ecx]
            //   c1cf51               | ror                 edi, 0x51
            //   647bda               | jnp                 0xffffffdd
            //   a0????????           |                     
            //   143b                 | adc                 al, 0x3b

        $sequence_6 = { 6bd1c3 4a 84d5 3910 07 d0c3 4a }
            // n = 7, score = 100
            //   6bd1c3               | imul                edx, ecx, -0x3d
            //   4a                   | dec                 edx
            //   84d5                 | test                ch, dl
            //   3910                 | cmp                 dword ptr [eax], edx
            //   07                   | pop                 es
            //   d0c3                 | rol                 bl, 1
            //   4a                   | dec                 edx

        $sequence_7 = { 47 49 43 53 49 4a 42 }
            // n = 7, score = 100
            //   47                   | inc                 edi
            //   49                   | dec                 ecx
            //   43                   | inc                 ebx
            //   53                   | push                ebx
            //   49                   | dec                 ecx
            //   4a                   | dec                 edx
            //   42                   | inc                 edx

        $sequence_8 = { ce 0238 0b7efd 829b5d40b7cfca 26fd 4f ce }
            // n = 7, score = 100
            //   ce                   | into                
            //   0238                 | add                 bh, byte ptr [eax]
            //   0b7efd               | or                  edi, dword ptr [esi - 3]
            //   829b5d40b7cfca       | sbb                 byte ptr [ebx - 0x3048bfa3], 0xca
            //   26fd                 | std                 
            //   4f                   | dec                 edi
            //   ce                   | into                

        $sequence_9 = { 41 4b 55 53 44 42 4d }
            // n = 7, score = 100
            //   41                   | inc                 ecx
            //   4b                   | dec                 ebx
            //   55                   | push                ebp
            //   53                   | push                ebx
            //   44                   | inc                 esp
            //   42                   | inc                 edx
            //   4d                   | dec                 ebp

    condition:
        7 of them and filesize < 4202496
}