rule win_silon_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.silon."
        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.silon"
        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 = { 8b4dfc 898158080000 81bd20efffffe5030000 746a 83bd18efffff00 7461 83bd1cefffff00 }
            // n = 7, score = 200
            //   8b4dfc               | mov                 ecx, dword ptr [ebp - 4]
            //   898158080000         | mov                 dword ptr [ecx + 0x858], eax
            //   81bd20efffffe5030000     | cmp    dword ptr [ebp - 0x10e0], 0x3e5
            //   746a                 | je                  0x6c
            //   83bd18efffff00       | cmp                 dword ptr [ebp - 0x10e8], 0
            //   7461                 | je                  0x63
            //   83bd1cefffff00       | cmp                 dword ptr [ebp - 0x10e4], 0

        $sequence_1 = { 68be358436 6a08 e8???????? 8945e4 6a00 ff55fc 8d55d4 }
            // n = 7, score = 200
            //   68be358436           | push                0x368435be
            //   6a08                 | push                8
            //   e8????????           |                     
            //   8945e4               | mov                 dword ptr [ebp - 0x1c], eax
            //   6a00                 | push                0
            //   ff55fc               | call                dword ptr [ebp - 4]
            //   8d55d4               | lea                 edx, [ebp - 0x2c]

        $sequence_2 = { 83c408 68???????? 8d95e8fdffff 52 e8???????? 83c408 68???????? }
            // n = 7, score = 200
            //   83c408               | add                 esp, 8
            //   68????????           |                     
            //   8d95e8fdffff         | lea                 edx, [ebp - 0x218]
            //   52                   | push                edx
            //   e8????????           |                     
            //   83c408               | add                 esp, 8
            //   68????????           |                     

        $sequence_3 = { 7512 8b55f0 0355ec c60200 }
            // n = 4, score = 200
            //   7512                 | jne                 0x14
            //   8b55f0               | mov                 edx, dword ptr [ebp - 0x10]
            //   0355ec               | add                 edx, dword ptr [ebp - 0x14]
            //   c60200               | mov                 byte ptr [edx], 0

        $sequence_4 = { 68???????? 68???????? 64a100000000 50 64892500000000 81c478fdffff }
            // n = 6, score = 200
            //   68????????           |                     
            //   68????????           |                     
            //   64a100000000         | mov                 eax, dword ptr fs:[0]
            //   50                   | push                eax
            //   64892500000000       | mov                 dword ptr fs:[0], esp
            //   81c478fdffff         | add                 esp, 0xfffffd78

        $sequence_5 = { 83c404 8945c8 837dc800 0f8488000000 8b55d0 52 e8???????? }
            // n = 7, score = 200
            //   83c404               | add                 esp, 4
            //   8945c8               | mov                 dword ptr [ebp - 0x38], eax
            //   837dc800             | cmp                 dword ptr [ebp - 0x38], 0
            //   0f8488000000         | je                  0x8e
            //   8b55d0               | mov                 edx, dword ptr [ebp - 0x30]
            //   52                   | push                edx
            //   e8????????           |                     

        $sequence_6 = { 6a00 6a02 8b4ddc 51 8b55d8 52 e8???????? }
            // n = 7, score = 200
            //   6a00                 | push                0
            //   6a02                 | push                2
            //   8b4ddc               | mov                 ecx, dword ptr [ebp - 0x24]
            //   51                   | push                ecx
            //   8b55d8               | mov                 edx, dword ptr [ebp - 0x28]
            //   52                   | push                edx
            //   e8????????           |                     

        $sequence_7 = { 83c410 6a0a 8b55e4 52 8d45d4 50 e8???????? }
            // n = 7, score = 200
            //   83c410               | add                 esp, 0x10
            //   6a0a                 | push                0xa
            //   8b55e4               | mov                 edx, dword ptr [ebp - 0x1c]
            //   52                   | push                edx
            //   8d45d4               | lea                 eax, [ebp - 0x2c]
            //   50                   | push                eax
            //   e8????????           |                     

        $sequence_8 = { 8d8568ffffff 50 6a03 8b4dec 51 }
            // n = 5, score = 200
            //   8d8568ffffff         | lea                 eax, [ebp - 0x98]
            //   50                   | push                eax
            //   6a03                 | push                3
            //   8b4dec               | mov                 ecx, dword ptr [ebp - 0x14]
            //   51                   | push                ecx

        $sequence_9 = { 8d95e8f9ffff 52 e8???????? 83c408 85c0 743e 68???????? }
            // n = 7, score = 200
            //   8d95e8f9ffff         | lea                 edx, [ebp - 0x618]
            //   52                   | push                edx
            //   e8????????           |                     
            //   83c408               | add                 esp, 8
            //   85c0                 | test                eax, eax
            //   743e                 | je                  0x40
            //   68????????           |                     

    condition:
        7 of them and filesize < 122880
}