rule win_evilbunny_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.evilbunny."
        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.evilbunny"
        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 = { 8b55e8 8902 8b45e8 c7400804000000 8b4d08 8b5108 83ea10 }
            // n = 7, score = 200
            //   8b55e8               | mov                 edx, dword ptr [ebp - 0x18]
            //   8902                 | mov                 dword ptr [edx], eax
            //   8b45e8               | mov                 eax, dword ptr [ebp - 0x18]
            //   c7400804000000       | mov                 dword ptr [eax + 8], 4
            //   8b4d08               | mov                 ecx, dword ptr [ebp + 8]
            //   8b5108               | mov                 edx, dword ptr [ecx + 8]
            //   83ea10               | sub                 edx, 0x10

        $sequence_1 = { e8???????? 8b4dfc 894108 8b55fc c7420400000000 8b45fc c70000000000 }
            // n = 7, score = 200
            //   e8????????           |                     
            //   8b4dfc               | mov                 ecx, dword ptr [ebp - 4]
            //   894108               | mov                 dword ptr [ecx + 8], eax
            //   8b55fc               | mov                 edx, dword ptr [ebp - 4]
            //   c7420400000000       | mov                 dword ptr [edx + 4], 0
            //   8b45fc               | mov                 eax, dword ptr [ebp - 4]
            //   c70000000000         | mov                 dword ptr [eax], 0

        $sequence_2 = { 8b4dfc 0fb65105 8b45f0 0fb64814 83f103 23d1 83e203 }
            // n = 7, score = 200
            //   8b4dfc               | mov                 ecx, dword ptr [ebp - 4]
            //   0fb65105             | movzx               edx, byte ptr [ecx + 5]
            //   8b45f0               | mov                 eax, dword ptr [ebp - 0x10]
            //   0fb64814             | movzx               ecx, byte ptr [eax + 0x14]
            //   83f103               | xor                 ecx, 3
            //   23d1                 | and                 edx, ecx
            //   83e203               | and                 edx, 3

        $sequence_3 = { 8b4dfc e8???????? 8b4dfc c701???????? 8b45fc 83c408 3bec }
            // n = 7, score = 200
            //   8b4dfc               | mov                 ecx, dword ptr [ebp - 4]
            //   e8????????           |                     
            //   8b4dfc               | mov                 ecx, dword ptr [ebp - 4]
            //   c701????????         |                     
            //   8b45fc               | mov                 eax, dword ptr [ebp - 4]
            //   83c408               | add                 esp, 8
            //   3bec                 | cmp                 ebp, esp

        $sequence_4 = { 8b550c 8b420c 837c080800 7445 8b4dfc c1e104 8b550c }
            // n = 7, score = 200
            //   8b550c               | mov                 edx, dword ptr [ebp + 0xc]
            //   8b420c               | mov                 eax, dword ptr [edx + 0xc]
            //   837c080800           | cmp                 dword ptr [eax + ecx + 8], 0
            //   7445                 | je                  0x47
            //   8b4dfc               | mov                 ecx, dword ptr [ebp - 4]
            //   c1e104               | shl                 ecx, 4
            //   8b550c               | mov                 edx, dword ptr [ebp + 0xc]

        $sequence_5 = { c705????????00000000 eb0c 8b55e0 52 e8???????? 83c404 6a08 }
            // n = 7, score = 200
            //   c705????????00000000     |     
            //   eb0c                 | jmp                 0xe
            //   8b55e0               | mov                 edx, dword ptr [ebp - 0x20]
            //   52                   | push                edx
            //   e8????????           |                     
            //   83c404               | add                 esp, 4
            //   6a08                 | push                8

        $sequence_6 = { e8???????? 83c408 85c0 0f84fc000000 8d8da0eeffff 51 8b55f8 }
            // n = 7, score = 200
            //   e8????????           |                     
            //   83c408               | add                 esp, 8
            //   85c0                 | test                eax, eax
            //   0f84fc000000         | je                  0x102
            //   8d8da0eeffff         | lea                 ecx, [ebp - 0x1160]
            //   51                   | push                ecx
            //   8b55f8               | mov                 edx, dword ptr [ebp - 8]

        $sequence_7 = { c1e202 52 8b45fc 8b4830 c1e102 51 8b55fc }
            // n = 7, score = 200
            //   c1e202               | shl                 edx, 2
            //   52                   | push                edx
            //   8b45fc               | mov                 eax, dword ptr [ebp - 4]
            //   8b4830               | mov                 ecx, dword ptr [eax + 0x30]
            //   c1e102               | shl                 ecx, 2
            //   51                   | push                ecx
            //   8b55fc               | mov                 edx, dword ptr [ebp - 4]

        $sequence_8 = { 51 e8???????? 83c404 8b55ec 8902 8b45ec c7400801000000 }
            // n = 7, score = 200
            //   51                   | push                ecx
            //   e8????????           |                     
            //   83c404               | add                 esp, 4
            //   8b55ec               | mov                 edx, dword ptr [ebp - 0x14]
            //   8902                 | mov                 dword ptr [edx], eax
            //   8b45ec               | mov                 eax, dword ptr [ebp - 0x14]
            //   c7400801000000       | mov                 dword ptr [eax + 8], 1

        $sequence_9 = { c745dc00000000 8bf4 68e8030000 ff15???????? 3bf4 e8???????? 8b45e0 }
            // n = 7, score = 200
            //   c745dc00000000       | mov                 dword ptr [ebp - 0x24], 0
            //   8bf4                 | mov                 esi, esp
            //   68e8030000           | push                0x3e8
            //   ff15????????         |                     
            //   3bf4                 | cmp                 esi, esp
            //   e8????????           |                     
            //   8b45e0               | mov                 eax, dword ptr [ebp - 0x20]

    condition:
        7 of them and filesize < 1695744
}