rule win_icefog_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.icefog."
        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.icefog"
        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 = { e8???????? 8b5508 8b430c 52 50 57 e8???????? }
            // n = 7, score = 200
            //   e8????????           |                     
            //   8b5508               | mov                 edx, dword ptr [ebp + 8]
            //   8b430c               | mov                 eax, dword ptr [ebx + 0xc]
            //   52                   | push                edx
            //   50                   | push                eax
            //   57                   | push                edi
            //   e8????????           |                     

        $sequence_1 = { 8d7801 83f701 4f 83c0ed 897df4 83f83b 0f8798010000 }
            // n = 7, score = 200
            //   8d7801               | lea                 edi, [eax + 1]
            //   83f701               | xor                 edi, 1
            //   4f                   | dec                 edi
            //   83c0ed               | add                 eax, -0x13
            //   897df4               | mov                 dword ptr [ebp - 0xc], edi
            //   83f83b               | cmp                 eax, 0x3b
            //   0f8798010000         | ja                  0x19e

        $sequence_2 = { 8b95a8feffff 894b38 89533c 8b4818 894b2c 8b5014 3b5024 }
            // n = 7, score = 200
            //   8b95a8feffff         | mov                 edx, dword ptr [ebp - 0x158]
            //   894b38               | mov                 dword ptr [ebx + 0x38], ecx
            //   89533c               | mov                 dword ptr [ebx + 0x3c], edx
            //   8b4818               | mov                 ecx, dword ptr [eax + 0x18]
            //   894b2c               | mov                 dword ptr [ebx + 0x2c], ecx
            //   8b5014               | mov                 edx, dword ptr [eax + 0x14]
            //   3b5024               | cmp                 edx, dword ptr [eax + 0x24]

        $sequence_3 = { e8???????? 8b5d20 8b55f8 53 52 6a6d 56 }
            // n = 7, score = 200
            //   e8????????           |                     
            //   8b5d20               | mov                 ebx, dword ptr [ebp + 0x20]
            //   8b55f8               | mov                 edx, dword ptr [ebp - 8]
            //   53                   | push                ebx
            //   52                   | push                edx
            //   6a6d                 | push                0x6d
            //   56                   | push                esi

        $sequence_4 = { 8b4df8 50 68???????? 51 e8???????? 83c40c eb10 }
            // n = 7, score = 200
            //   8b4df8               | mov                 ecx, dword ptr [ebp - 8]
            //   50                   | push                eax
            //   68????????           |                     
            //   51                   | push                ecx
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc
            //   eb10                 | jmp                 0x12

        $sequence_5 = { 8d46c4 50 53 895de0 e8???????? 83c418 837ee400 }
            // n = 7, score = 200
            //   8d46c4               | lea                 eax, [esi - 0x3c]
            //   50                   | push                eax
            //   53                   | push                ebx
            //   895de0               | mov                 dword ptr [ebp - 0x20], ebx
            //   e8????????           |                     
            //   83c418               | add                 esp, 0x18
            //   837ee400             | cmp                 dword ptr [esi - 0x1c], 0

        $sequence_6 = { 8b4ddc 8b5508 833c9100 7e18 8b45f8 8b4d08 6a00 }
            // n = 7, score = 200
            //   8b4ddc               | mov                 ecx, dword ptr [ebp - 0x24]
            //   8b5508               | mov                 edx, dword ptr [ebp + 8]
            //   833c9100             | cmp                 dword ptr [ecx + edx*4], 0
            //   7e18                 | jle                 0x1a
            //   8b45f8               | mov                 eax, dword ptr [ebp - 8]
            //   8b4d08               | mov                 ecx, dword ptr [ebp + 8]
            //   6a00                 | push                0

        $sequence_7 = { 8b04d0 50 8945f8 e8???????? 8b55fc 8d0c00 83e201 }
            // n = 7, score = 200
            //   8b04d0               | mov                 eax, dword ptr [eax + edx*8]
            //   50                   | push                eax
            //   8945f8               | mov                 dword ptr [ebp - 8], eax
            //   e8????????           |                     
            //   8b55fc               | mov                 edx, dword ptr [ebp - 4]
            //   8d0c00               | lea                 ecx, [eax + eax]
            //   83e201               | and                 edx, 1

        $sequence_8 = { 8945dc 8b45e0 33db 83c404 3918 7e4b 895dd4 }
            // n = 7, score = 200
            //   8945dc               | mov                 dword ptr [ebp - 0x24], eax
            //   8b45e0               | mov                 eax, dword ptr [ebp - 0x20]
            //   33db                 | xor                 ebx, ebx
            //   83c404               | add                 esp, 4
            //   3918                 | cmp                 dword ptr [eax], ebx
            //   7e4b                 | jle                 0x4d
            //   895dd4               | mov                 dword ptr [ebp - 0x2c], ebx

        $sequence_9 = { 898578ffffff 0fb75310 8b7d0c 46 897590 3bf2 0f8c9afeffff }
            // n = 7, score = 200
            //   898578ffffff         | mov                 dword ptr [ebp - 0x88], eax
            //   0fb75310             | movzx               edx, word ptr [ebx + 0x10]
            //   8b7d0c               | mov                 edi, dword ptr [ebp + 0xc]
            //   46                   | inc                 esi
            //   897590               | mov                 dword ptr [ebp - 0x70], esi
            //   3bf2                 | cmp                 esi, edx
            //   0f8c9afeffff         | jl                  0xfffffea0

    condition:
        7 of them and filesize < 1187840
}