rule win_mydoom_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.mydoom."
        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.mydoom"
        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 = { ba00000000 84c0 0f84b1000000 0fbec3 }
            // n = 4, score = 100
            //   ba00000000           | mov                 edx, 0
            //   84c0                 | test                al, al
            //   0f84b1000000         | je                  0xb7
            //   0fbec3               | movsx               eax, bl

        $sequence_1 = { ba00000000 85c0 0f84ac000000 8d8538ffffff 89442404 c70424???????? e8???????? }
            // n = 7, score = 100
            //   ba00000000           | mov                 edx, 0
            //   85c0                 | test                eax, eax
            //   0f84ac000000         | je                  0xb2
            //   8d8538ffffff         | lea                 eax, [ebp - 0xc8]
            //   89442404             | mov                 dword ptr [esp + 4], eax
            //   c70424????????       |                     
            //   e8????????           |                     

        $sequence_2 = { c745d805040003 0fb645d7 8845ec c744240805000000 8d45d8 89442404 893424 }
            // n = 7, score = 100
            //   c745d805040003       | mov                 dword ptr [ebp - 0x28], 0x3000405
            //   0fb645d7             | movzx               eax, byte ptr [ebp - 0x29]
            //   8845ec               | mov                 byte ptr [ebp - 0x14], al
            //   c744240805000000     | mov                 dword ptr [esp + 8], 5
            //   8d45d8               | lea                 eax, [ebp - 0x28]
            //   89442404             | mov                 dword ptr [esp + 4], eax
            //   893424               | mov                 dword ptr [esp], esi

        $sequence_3 = { 74ef 84db 7ff1 0fbe45f3 c1e008 }
            // n = 5, score = 100
            //   74ef                 | je                  0xfffffff1
            //   84db                 | test                bl, bl
            //   7ff1                 | jg                  0xfffffff3
            //   0fbe45f3             | movsx               eax, byte ptr [ebp - 0xd]
            //   c1e008               | shl                 eax, 8

        $sequence_4 = { b800000000 e9???????? 8b830c040000 800801 c744240402000000 8b4304 }
            // n = 6, score = 100
            //   b800000000           | mov                 eax, 0
            //   e9????????           |                     
            //   8b830c040000         | mov                 eax, dword ptr [ebx + 0x40c]
            //   800801               | or                  byte ptr [eax], 1
            //   c744240402000000     | mov                 dword ptr [esp + 4], 2
            //   8b4304               | mov                 eax, dword ptr [ebx + 4]

        $sequence_5 = { 57 48 f2ae 55 ff967cb00000 }
            // n = 5, score = 100
            //   57                   | push                edi
            //   48                   | dec                 eax
            //   f2ae                 | repne scasb         al, byte ptr es:[edi]
            //   55                   | push                ebp
            //   ff967cb00000         | call                dword ptr [esi + 0xb07c]

        $sequence_6 = { 891424 e8???????? 31d2 8915???????? }
            // n = 4, score = 100
            //   891424               | mov                 dword ptr [esp], edx
            //   e8????????           |                     
            //   31d2                 | xor                 edx, edx
            //   8915????????         |                     

        $sequence_7 = { c20c00 c7042480000000 e8???????? a3???????? 85c0 }
            // n = 5, score = 100
            //   c20c00               | ret                 0xc
            //   c7042480000000       | mov                 dword ptr [esp], 0x80
            //   e8????????           |                     
            //   a3????????           |                     
            //   85c0                 | test                eax, eax

        $sequence_8 = { 8b4518 89442404 893424 e8???????? ba00000000 e9???????? 8b420c }
            // n = 7, score = 100
            //   8b4518               | mov                 eax, dword ptr [ebp + 0x18]
            //   89442404             | mov                 dword ptr [esp + 4], eax
            //   893424               | mov                 dword ptr [esp], esi
            //   e8????????           |                     
            //   ba00000000           | mov                 edx, 0
            //   e9????????           |                     
            //   8b420c               | mov                 eax, dword ptr [edx + 0xc]

        $sequence_9 = { 85d0 7547 85f6 750c 8b0d???????? 85c9 7546 }
            // n = 7, score = 100
            //   85d0                 | test                eax, edx
            //   7547                 | jne                 0x49
            //   85f6                 | test                esi, esi
            //   750c                 | jne                 0xe
            //   8b0d????????         |                     
            //   85c9                 | test                ecx, ecx
            //   7546                 | jne                 0x48

    condition:
        7 of them and filesize < 114688
}