rule win_postnaptea_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.postnaptea."
        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.postnaptea"
        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 = { 4c8930 488b4638 4c8930 488b4650 448930 488d053ebf0600 488906 }
            // n = 7, score = 100
            //   4c8930               | add                 ecx, edx
            //   488b4638             | inc                 ecx
            //   4c8930               | add                 dword ptr [edx + 4], ecx
            //   488b4650             | inc                 ecx
            //   448930               | add                 dword ptr [edx + 8], edx
            //   488d053ebf0600       | inc                 ecx
            //   488906               | mov                 dword ptr [eax + edx*4], eax

        $sequence_1 = { f30f1084059c060000 f30f58840598060000 f30f118c8d900a0000 f30f104c058c f30f584c0588 f30f588405d8060000 f30f584c05c8 }
            // n = 7, score = 100
            //   f30f1084059c060000     | dec    eax
            //   f30f58840598060000     | test    eax, eax
            //   f30f118c8d900a0000     | je    0x3ed
            //   f30f104c058c         | mov                 dword ptr [esp + 0x78], 0x18
            //   f30f584c0588         | dec                 eax
            //   f30f588405d8060000     | lea    ecx, [ebp - 0x60]
            //   f30f584c05c8         | dec                 eax

        $sequence_2 = { c745a4a00f0000 48895de8 33d2 41b880000000 488d8d40130000 e8???????? 33d2 }
            // n = 7, score = 100
            //   c745a4a00f0000       | mov                 dword ptr [ebp - 0x31], edi
            //   48895de8             | dec                 eax
            //   33d2                 | test                edi, edi
            //   41b880000000         | jne                 0xa1d
            //   488d8d40130000       | inc                 ebp
            //   e8????????           |                     
            //   33d2                 | xor                 eax, eax

        $sequence_3 = { e8???????? 4c8b05???????? 488905???????? 498bc8 ffd0 4c8b05???????? 4d85c0 }
            // n = 7, score = 100
            //   e8????????           |                     
            //   4c8b05????????       |                     
            //   488905????????       |                     
            //   498bc8               | dec                 eax
            //   ffd0                 | add                 ebx, 6
            //   4c8b05????????       |                     
            //   4d85c0               | jmp                 0xd21

        $sequence_4 = { c7456cd4f588f5 c7457093f5a0f5 c74574c2f5c2f5 c74578def5daf5 c7457ccef5def5 c78580000000d2f5d7f5 c7858400000093f5dbf5 }
            // n = 7, score = 100
            //   c7456cd4f588f5       | mov                 eax, dword ptr [ecx]
            //   c7457093f5a0f5       | call                dword ptr [eax + 0x10]
            //   c74574c2f5c2f5       | dec                 eax
            //   c74578def5daf5       | mov                 eax, dword ptr [ecx]
            //   c7457ccef5def5       | call                dword ptr [eax + 0x10]
            //   c78580000000d2f5d7f5     | dec    eax
            //   c7858400000093f5dbf5     | mov    ecx, dword ptr [ebp + 0x18]

        $sequence_5 = { c7858c000000eaf5b0f5 c78590000000abf5b2f5 c78594000000b6f5f0f5 33c0 66898598000000 418bd6 0f1f840000000000 }
            // n = 7, score = 100
            //   c7858c000000eaf5b0f5     | mov    edx, dword ptr [ebp - 0x78]
            //   c78590000000abf5b2f5     | dec    eax
            //   c78594000000b6f5f0f5     | cmp    edx, 0x10
            //   33c0                 | jb                  0x18a0
            //   66898598000000       | dec                 eax
            //   418bd6               | inc                 edx
            //   0f1f840000000000     | dec                 eax

        $sequence_6 = { e8???????? 488905???????? 498bcd ffd0 488b4de8 ff15???????? 488b4df0 }
            // n = 7, score = 100
            //   e8????????           |                     
            //   488905????????       |                     
            //   498bcd               | inc                 ecx
            //   ffd0                 | inc                 eax
            //   488b4de8             | inc                 ecx
            //   ff15????????         |                     
            //   488b4df0             | cmp                 eax, 3

        $sequence_7 = { ffd0 448be8 85c0 740b 3d03010000 0f85b7010000 8b4d03 }
            // n = 7, score = 100
            //   ffd0                 | mov                 dword ptr [ebp + 0x66c], 0xf51ef57b
            //   448be8               | mov                 dword ptr [ebp + 0x670], 0xf537f528
            //   85c0                 | mov                 dword ptr [ebp + 0x674], 0xf504f533
            //   740b                 | mov                 dword ptr [ebp + 0x678], 0xf536f541
            //   3d03010000           | dec                 eax
            //   0f85b7010000         | lea                 ecx, [ebp + 0xf10]
            //   8b4d03               | mov                 dword ptr [ebp + 0xb70], 0xf533f50f

        $sequence_8 = { c785f80000007cf577f5 c785fc00000069f56bf5 c785000100002ef50000 418bd0 660f1f840000000000 4863c2 488d8df8000000 }
            // n = 7, score = 100
            //   c785f80000007cf577f5     | je    0x1873
            //   c785fc00000069f56bf5     | dec    eax
            //   c785000100002ef50000     | mov    eax, dword ptr [ecx]
            //   418bd0               | call                dword ptr [eax + 0x20]
            //   660f1f840000000000     | dec    eax
            //   4863c2               | lea                 eax, [0x4d853]
            //   488d8df8000000       | dec                 eax

        $sequence_9 = { c785c0040000eaf5e5f5 c785c4040000eff5e9f5 c785c8040000adf5b4f5 c785cc040000aff50000 33ff 8bd7 0f1f840000000000 }
            // n = 7, score = 100
            //   c785c0040000eaf5e5f5     | dec    eax
            //   c785c4040000eff5e9f5     | cmove    ebx, eax
            //   c785c8040000adf5b4f5     | dec    eax
            //   c785cc040000aff50000     | mov    edx, ebx
            //   33ff                 | dec                 eax
            //   8bd7                 | mov                 ebx, dword ptr [esp + 0x30]
            //   0f1f840000000000     | dec                 eax

    condition:
        7 of them and filesize < 2457600
}