rule win_squirrelwaffle_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.squirrelwaffle."
        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.squirrelwaffle"
        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 = { 8a01 41 84c0 75f9 6a00 2bce 8bb564f7ffff }
            // n = 7, score = 700
            //   8a01                 | mov                 al, byte ptr [ecx]
            //   41                   | inc                 ecx
            //   84c0                 | test                al, al
            //   75f9                 | jne                 0xfffffffb
            //   6a00                 | push                0
            //   2bce                 | sub                 ecx, esi
            //   8bb564f7ffff         | mov                 esi, dword ptr [ebp - 0x89c]

        $sequence_1 = { 0f434508 8d8d40ffffff 6a02 50 }
            // n = 4, score = 700
            //   0f434508             | cmovae              eax, dword ptr [ebp + 8]
            //   8d8d40ffffff         | lea                 ecx, [ebp - 0xc0]
            //   6a02                 | push                2
            //   50                   | push                eax

        $sequence_2 = { 85c0 751a 50 8b8540ffffff 8d8d40ffffff 6a02 8b4004 }
            // n = 7, score = 700
            //   85c0                 | test                eax, eax
            //   751a                 | jne                 0x1c
            //   50                   | push                eax
            //   8b8540ffffff         | mov                 eax, dword ptr [ebp - 0xc0]
            //   8d8d40ffffff         | lea                 ecx, [ebp - 0xc0]
            //   6a02                 | push                2
            //   8b4004               | mov                 eax, dword ptr [eax + 4]

        $sequence_3 = { 33f6 0f1f4000 0f1f840000000000 833d????????10 bb???????? }
            // n = 5, score = 700
            //   33f6                 | xor                 esi, esi
            //   0f1f4000             | nop                 dword ptr [eax]
            //   0f1f840000000000     | nop                 dword ptr [eax + eax]
            //   833d????????10       |                     
            //   bb????????           |                     

        $sequence_4 = { 83ceff 8b55e8 83fa10 0f8278000000 8b4dd4 42 }
            // n = 6, score = 700
            //   83ceff               | or                  esi, 0xffffffff
            //   8b55e8               | mov                 edx, dword ptr [ebp - 0x18]
            //   83fa10               | cmp                 edx, 0x10
            //   0f8278000000         | jb                  0x7e
            //   8b4dd4               | mov                 ecx, dword ptr [ebp - 0x2c]
            //   42                   | inc                 edx

        $sequence_5 = { 8d45ed c7855cf7ffff00000000 c78560f7ffff0f000000 c6854cf7ffff00 3bf0 740f 2bc6 }
            // n = 7, score = 700
            //   8d45ed               | lea                 eax, [ebp - 0x13]
            //   c7855cf7ffff00000000     | mov    dword ptr [ebp - 0x8a4], 0
            //   c78560f7ffff0f000000     | mov    dword ptr [ebp - 0x8a0], 0xf
            //   c6854cf7ffff00       | mov                 byte ptr [ebp - 0x8b4], 0
            //   3bf0                 | cmp                 esi, eax
            //   740f                 | je                  0x11
            //   2bc6                 | sub                 eax, esi

        $sequence_6 = { c645c400 8d4dd4 ff75c4 6a08 e8???????? e9???????? }
            // n = 6, score = 700
            //   c645c400             | mov                 byte ptr [ebp - 0x3c], 0
            //   8d4dd4               | lea                 ecx, [ebp - 0x2c]
            //   ff75c4               | push                dword ptr [ebp - 0x3c]
            //   6a08                 | push                8
            //   e8????????           |                     
            //   e9????????           |                     

        $sequence_7 = { c785c0f6ffff00000000 c785c4f6ffff0f000000 c685b0f6ffff00 c645fc22 }
            // n = 4, score = 700
            //   c785c0f6ffff00000000     | mov    dword ptr [ebp - 0x940], 0
            //   c785c4f6ffff0f000000     | mov    dword ptr [ebp - 0x93c], 0xf
            //   c685b0f6ffff00       | mov                 byte ptr [ebp - 0x950], 0
            //   c645fc22             | mov                 byte ptr [ebp - 4], 0x22

        $sequence_8 = { 89956cf9ffff ff15???????? 83c408 898580f7ffff }
            // n = 4, score = 700
            //   89956cf9ffff         | mov                 dword ptr [ebp - 0x694], edx
            //   ff15????????         |                     
            //   83c408               | add                 esp, 8
            //   898580f7ffff         | mov                 dword ptr [ebp - 0x880], eax

        $sequence_9 = { 7230 83fa10 8db5b0f6ffff 8d4112 0f43b5b0f6ffff }
            // n = 5, score = 700
            //   7230                 | jb                  0x32
            //   83fa10               | cmp                 edx, 0x10
            //   8db5b0f6ffff         | lea                 esi, [ebp - 0x950]
            //   8d4112               | lea                 eax, [ecx + 0x12]
            //   0f43b5b0f6ffff       | cmovae              esi, dword ptr [ebp - 0x950]

    condition:
        7 of them and filesize < 147456
}