rule win_milkmaid_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.milkmaid."
        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.milkmaid"
        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 = { ff15???????? 8b74241c 8d4c2404 51 }
            // n = 4, score = 100
            //   ff15????????         |                     
            //   8b74241c             | mov                 esi, dword ptr [esp + 0x1c]
            //   8d4c2404             | lea                 ecx, [esp + 4]
            //   51                   | push                ecx

        $sequence_1 = { c68424e428010003 e8???????? b911000000 33c0 8d7c2434 33d2 }
            // n = 6, score = 100
            //   c68424e428010003     | mov                 byte ptr [esp + 0x128e4], 3
            //   e8????????           |                     
            //   b911000000           | mov                 ecx, 0x11
            //   33c0                 | xor                 eax, eax
            //   8d7c2434             | lea                 edi, [esp + 0x34]
            //   33d2                 | xor                 edx, edx

        $sequence_2 = { eb05 8b5708 2bd1 8b5c2428 8b6c242c 8d4c0201 894704 }
            // n = 7, score = 100
            //   eb05                 | jmp                 7
            //   8b5708               | mov                 edx, dword ptr [edi + 8]
            //   2bd1                 | sub                 edx, ecx
            //   8b5c2428             | mov                 ebx, dword ptr [esp + 0x28]
            //   8b6c242c             | mov                 ebp, dword ptr [esp + 0x2c]
            //   8d4c0201             | lea                 ecx, [edx + eax + 1]
            //   894704               | mov                 dword ptr [edi + 4], eax

        $sequence_3 = { 8b442410 8b4c240c 50 51 8d8c2480000000 c68424e428010003 }
            // n = 6, score = 100
            //   8b442410             | mov                 eax, dword ptr [esp + 0x10]
            //   8b4c240c             | mov                 ecx, dword ptr [esp + 0xc]
            //   50                   | push                eax
            //   51                   | push                ecx
            //   8d8c2480000000       | lea                 ecx, [esp + 0x80]
            //   c68424e428010003     | mov                 byte ptr [esp + 0x128e4], 3

        $sequence_4 = { 53 8d4c2434 89542454 c784248400000001000000 }
            // n = 4, score = 100
            //   53                   | push                ebx
            //   8d4c2434             | lea                 ecx, [esp + 0x34]
            //   89542454             | mov                 dword ptr [esp + 0x54], edx
            //   c784248400000001000000     | mov    dword ptr [esp + 0x84], 1

        $sequence_5 = { 896c2420 8a8528280100 84c0 7528 8b4d04 8d450c 51 }
            // n = 7, score = 100
            //   896c2420             | mov                 dword ptr [esp + 0x20], ebp
            //   8a8528280100         | mov                 al, byte ptr [ebp + 0x12828]
            //   84c0                 | test                al, al
            //   7528                 | jne                 0x2a
            //   8b4d04               | mov                 ecx, dword ptr [ebp + 4]
            //   8d450c               | lea                 eax, [ebp + 0xc]
            //   51                   | push                ecx

        $sequence_6 = { 8d4c2410 c68424dc28010001 e8???????? 8d4c2414 889c24dc280100 }
            // n = 5, score = 100
            //   8d4c2410             | lea                 ecx, [esp + 0x10]
            //   c68424dc28010001     | mov                 byte ptr [esp + 0x128dc], 1
            //   e8????????           |                     
            //   8d4c2414             | lea                 ecx, [esp + 0x14]
            //   889c24dc280100       | mov                 byte ptr [esp + 0x128dc], bl

        $sequence_7 = { 5e 5b 64890d00000000 81c4d4280100 c3 57 56 }
            // n = 7, score = 100
            //   5e                   | pop                 esi
            //   5b                   | pop                 ebx
            //   64890d00000000       | mov                 dword ptr fs:[0], ecx
            //   81c4d4280100         | add                 esp, 0x128d4
            //   c3                   | ret                 
            //   57                   | push                edi
            //   56                   | push                esi

    condition:
        7 of them and filesize < 65536
}