rule win_petya_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.petya."
        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.petya"
        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 = { 83c050 03c7 53 50 e8???????? 83c40c }
            // n = 6, score = 600
            //   83c050               | add                 eax, 0x50
            //   03c7                 | add                 eax, edi
            //   53                   | push                ebx
            //   50                   | push                eax
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc

        $sequence_1 = { 33ff 3b750c 0f47d9 85db 7410 8b06 85c0 }
            // n = 7, score = 600
            //   33ff                 | xor                 edi, edi
            //   3b750c               | cmp                 esi, dword ptr [ebp + 0xc]
            //   0f47d9               | cmova               ebx, ecx
            //   85db                 | test                ebx, ebx
            //   7410                 | je                  0x12
            //   8b06                 | mov                 eax, dword ptr [esi]
            //   85c0                 | test                eax, eax

        $sequence_2 = { 53 e8???????? 8b4604 83c40c 8b4e08 }
            // n = 5, score = 600
            //   53                   | push                ebx
            //   e8????????           |                     
            //   8b4604               | mov                 eax, dword ptr [esi + 4]
            //   83c40c               | add                 esp, 0xc
            //   8b4e08               | mov                 ecx, dword ptr [esi + 8]

        $sequence_3 = { 33c9 57 33ff 8d0486 8bd8 2bde 83c303 }
            // n = 7, score = 600
            //   33c9                 | xor                 ecx, ecx
            //   57                   | push                edi
            //   33ff                 | xor                 edi, edi
            //   8d0486               | lea                 eax, [esi + eax*4]
            //   8bd8                 | mov                 ebx, eax
            //   2bde                 | sub                 ebx, esi
            //   83c303               | add                 ebx, 3

        $sequence_4 = { 03ce 13c2 03cb 894c243c }
            // n = 4, score = 600
            //   03ce                 | add                 ecx, esi
            //   13c2                 | adc                 eax, edx
            //   03cb                 | add                 ecx, ebx
            //   894c243c             | mov                 dword ptr [esp + 0x3c], ecx

        $sequence_5 = { 53 50 e8???????? 83c40c 8d5750 8bcf e8???????? }
            // n = 7, score = 600
            //   53                   | push                ebx
            //   50                   | push                eax
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc
            //   8d5750               | lea                 edx, [edi + 0x50]
            //   8bcf                 | mov                 ecx, edi
            //   e8????????           |                     

        $sequence_6 = { 57 33ff 3b750c 0f47d9 85db 7410 8b06 }
            // n = 7, score = 600
            //   57                   | push                edi
            //   33ff                 | xor                 edi, edi
            //   3b750c               | cmp                 esi, dword ptr [ebp + 0xc]
            //   0f47d9               | cmova               ebx, ecx
            //   85db                 | test                ebx, ebx
            //   7410                 | je                  0x12
            //   8b06                 | mov                 eax, dword ptr [esi]

        $sequence_7 = { 68???????? 68???????? ff15???????? 50 ff15???????? 8d4df8 51 }
            // n = 7, score = 600
            //   68????????           |                     
            //   68????????           |                     
            //   ff15????????         |                     
            //   50                   | push                eax
            //   ff15????????         |                     
            //   8d4df8               | lea                 ecx, [ebp - 8]
            //   51                   | push                ecx

        $sequence_8 = { 83c303 c1eb02 57 33ff 3b750c 0f47d9 }
            // n = 6, score = 600
            //   83c303               | add                 ebx, 3
            //   c1eb02               | shr                 ebx, 2
            //   57                   | push                edi
            //   33ff                 | xor                 edi, edi
            //   3b750c               | cmp                 esi, dword ptr [ebp + 0xc]
            //   0f47d9               | cmova               ebx, ecx

        $sequence_9 = { 85f6 7505 e8???????? 8bc7 5f }
            // n = 5, score = 600
            //   85f6                 | test                esi, esi
            //   7505                 | jne                 7
            //   e8????????           |                     
            //   8bc7                 | mov                 eax, edi
            //   5f                   | pop                 edi

    condition:
        7 of them and filesize < 229376
}