rule win_frozenhill_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.frozenhill."
        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.frozenhill"
        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 = { 8b0485507c1310 8a4c102d 80e1fe 8b55e0 c1fa06 8b45e0 83e03f }
            // n = 7, score = 100
            //   8b0485507c1310       | mov                 eax, dword ptr [eax*4 + 0x10137c50]
            //   8a4c102d             | mov                 cl, byte ptr [eax + edx + 0x2d]
            //   80e1fe               | and                 cl, 0xfe
            //   8b55e0               | mov                 edx, dword ptr [ebp - 0x20]
            //   c1fa06               | sar                 edx, 6
            //   8b45e0               | mov                 eax, dword ptr [ebp - 0x20]
            //   83e03f               | and                 eax, 0x3f

        $sequence_1 = { 6a72 58 668985a6fdffff 6a61 58 668985a8fdffff 6a6d }
            // n = 7, score = 100
            //   6a72                 | push                0x72
            //   58                   | pop                 eax
            //   668985a6fdffff       | mov                 word ptr [ebp - 0x25a], ax
            //   6a61                 | push                0x61
            //   58                   | pop                 eax
            //   668985a8fdffff       | mov                 word ptr [ebp - 0x258], ax
            //   6a6d                 | push                0x6d

        $sequence_2 = { ff15???????? 3bf4 e8???????? 8945e0 837decff 7507 c745ec80000000 }
            // n = 7, score = 100
            //   ff15????????         |                     
            //   3bf4                 | cmp                 esi, esp
            //   e8????????           |                     
            //   8945e0               | mov                 dword ptr [ebp - 0x20], eax
            //   837decff             | cmp                 dword ptr [ebp - 0x14], -1
            //   7507                 | jne                 9
            //   c745ec80000000       | mov                 dword ptr [ebp - 0x14], 0x80

        $sequence_3 = { 81c1???????? 51 8b5510 8b02 0345c4 50 }
            // n = 6, score = 100
            //   81c1????????         |                     
            //   51                   | push                ecx
            //   8b5510               | mov                 edx, dword ptr [ebp + 0x10]
            //   8b02                 | mov                 eax, dword ptr [edx]
            //   0345c4               | add                 eax, dword ptr [ebp - 0x3c]
            //   50                   | push                eax

        $sequence_4 = { 50 8b4df4 51 e8???????? 85c0 7583 8bf4 }
            // n = 7, score = 100
            //   50                   | push                eax
            //   8b4df4               | mov                 ecx, dword ptr [ebp - 0xc]
            //   51                   | push                ecx
            //   e8????????           |                     
            //   85c0                 | test                eax, eax
            //   7583                 | jne                 0xffffff85
            //   8bf4                 | mov                 esi, esp

        $sequence_5 = { b872000000 668945a4 b865000000 668945a6 b85c000000 668945a8 b84d000000 }
            // n = 7, score = 100
            //   b872000000           | mov                 eax, 0x72
            //   668945a4             | mov                 word ptr [ebp - 0x5c], ax
            //   b865000000           | mov                 eax, 0x65
            //   668945a6             | mov                 word ptr [ebp - 0x5a], ax
            //   b85c000000           | mov                 eax, 0x5c
            //   668945a8             | mov                 word ptr [ebp - 0x58], ax
            //   b84d000000           | mov                 eax, 0x4d

        $sequence_6 = { 8d8520ffffff 50 8b4df8 e8???????? 8b08 898d2cffffff 8b5508 }
            // n = 7, score = 100
            //   8d8520ffffff         | lea                 eax, [ebp - 0xe0]
            //   50                   | push                eax
            //   8b4df8               | mov                 ecx, dword ptr [ebp - 8]
            //   e8????????           |                     
            //   8b08                 | mov                 ecx, dword ptr [eax]
            //   898d2cffffff         | mov                 dword ptr [ebp - 0xd4], ecx
            //   8b5508               | mov                 edx, dword ptr [ebp + 8]

        $sequence_7 = { c645fc00 8d8df4feffff e8???????? 0fb6850bffffff 85c0 744b }
            // n = 6, score = 100
            //   c645fc00             | mov                 byte ptr [ebp - 4], 0
            //   8d8df4feffff         | lea                 ecx, [ebp - 0x10c]
            //   e8????????           |                     
            //   0fb6850bffffff       | movzx               eax, byte ptr [ebp - 0xf5]
            //   85c0                 | test                eax, eax
            //   744b                 | je                  0x4d

        $sequence_8 = { b8cccccccc f3ab b9???????? e8???????? 8b4508 8945f8 8b450c }
            // n = 7, score = 100
            //   b8cccccccc           | mov                 eax, 0xcccccccc
            //   f3ab                 | rep stosd           dword ptr es:[edi], eax
            //   b9????????           |                     
            //   e8????????           |                     
            //   8b4508               | mov                 eax, dword ptr [ebp + 8]
            //   8945f8               | mov                 dword ptr [ebp - 8], eax
            //   8b450c               | mov                 eax, dword ptr [ebp + 0xc]

        $sequence_9 = { b001 eb2e 8d85c4feffff 50 ffb5b8feffff e8???????? 8945f4 }
            // n = 7, score = 100
            //   b001                 | mov                 al, 1
            //   eb2e                 | jmp                 0x30
            //   8d85c4feffff         | lea                 eax, [ebp - 0x13c]
            //   50                   | push                eax
            //   ffb5b8feffff         | push                dword ptr [ebp - 0x148]
            //   e8????????           |                     
            //   8945f4               | mov                 dword ptr [ebp - 0xc], eax

    condition:
        7 of them and filesize < 2652160
}