rule win_cohhoc_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.cohhoc."
        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.cohhoc"
        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 = { 50 6804010000 ff15???????? 8b8c240c010000 8d542404 51 6a00 }
            // n = 7, score = 300
            //   50                   | push                eax
            //   6804010000           | push                0x104
            //   ff15????????         |                     
            //   8b8c240c010000       | mov                 ecx, dword ptr [esp + 0x10c]
            //   8d542404             | lea                 edx, [esp + 4]
            //   51                   | push                ecx
            //   6a00                 | push                0

        $sequence_1 = { 83e103 f3a4 8b4c241c 03c8 894c241c 8b4c2420 e8???????? }
            // n = 7, score = 300
            //   83e103               | and                 ecx, 3
            //   f3a4                 | rep movsb           byte ptr es:[edi], byte ptr [esi]
            //   8b4c241c             | mov                 ecx, dword ptr [esp + 0x1c]
            //   03c8                 | add                 ecx, eax
            //   894c241c             | mov                 dword ptr [esp + 0x1c], ecx
            //   8b4c2420             | mov                 ecx, dword ptr [esp + 0x20]
            //   e8????????           |                     

        $sequence_2 = { c705????????01000000 c705????????84000000 891d???????? 891d???????? }
            // n = 4, score = 300
            //   c705????????01000000     |     
            //   c705????????84000000     |     
            //   891d????????         |                     
            //   891d????????         |                     

        $sequence_3 = { f3ab 8b436c 33f6 3bc6 c744241401000000 }
            // n = 5, score = 300
            //   f3ab                 | rep stosd           dword ptr es:[edi], eax
            //   8b436c               | mov                 eax, dword ptr [ebx + 0x6c]
            //   33f6                 | xor                 esi, esi
            //   3bc6                 | cmp                 eax, esi
            //   c744241401000000     | mov                 dword ptr [esp + 0x14], 1

        $sequence_4 = { 6804010000 ff15???????? 8b8c240c010000 8d542404 }
            // n = 4, score = 300
            //   6804010000           | push                0x104
            //   ff15????????         |                     
            //   8b8c240c010000       | mov                 ecx, dword ptr [esp + 0x10c]
            //   8d542404             | lea                 edx, [esp + 4]

        $sequence_5 = { 75dc 33c0 eb05 1bc0 83d8ff 85c0 0f84ba000000 }
            // n = 7, score = 300
            //   75dc                 | jne                 0xffffffde
            //   33c0                 | xor                 eax, eax
            //   eb05                 | jmp                 7
            //   1bc0                 | sbb                 eax, eax
            //   83d8ff               | sbb                 eax, -1
            //   85c0                 | test                eax, eax
            //   0f84ba000000         | je                  0xc0

        $sequence_6 = { 8dbc2468010000 33c0 8d542420 f2ae f7d1 2bf9 }
            // n = 6, score = 300
            //   8dbc2468010000       | lea                 edi, [esp + 0x168]
            //   33c0                 | xor                 eax, eax
            //   8d542420             | lea                 edx, [esp + 0x20]
            //   f2ae                 | repne scasb         al, byte ptr es:[edi]
            //   f7d1                 | not                 ecx
            //   2bf9                 | sub                 edi, ecx

        $sequence_7 = { 8b442408 8bc8 80e107 f6d9 1bc9 }
            // n = 5, score = 300
            //   8b442408             | mov                 eax, dword ptr [esp + 8]
            //   8bc8                 | mov                 ecx, eax
            //   80e107               | and                 cl, 7
            //   f6d9                 | neg                 cl
            //   1bc9                 | sbb                 ecx, ecx

        $sequence_8 = { 57 6a0f ff15???????? 8b4c2458 8bf8 8d442414 50 }
            // n = 7, score = 300
            //   57                   | push                edi
            //   6a0f                 | push                0xf
            //   ff15????????         |                     
            //   8b4c2458             | mov                 ecx, dword ptr [esp + 0x58]
            //   8bf8                 | mov                 edi, eax
            //   8d442414             | lea                 eax, [esp + 0x14]
            //   50                   | push                eax

        $sequence_9 = { 83e203 c1f904 83e10f c1e204 8d4c0c10 }
            // n = 5, score = 300
            //   83e203               | and                 edx, 3
            //   c1f904               | sar                 ecx, 4
            //   83e10f               | and                 ecx, 0xf
            //   c1e204               | shl                 edx, 4
            //   8d4c0c10             | lea                 ecx, [esp + ecx + 0x10]

    condition:
        7 of them and filesize < 253952
}