rule win_ketrum_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.ketrum."
        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.ketrum"
        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 = { 037de4 8d8c0f53144402 c1c109 03c8 8bfe f7d7 23f8 }
            // n = 7, score = 200
            //   037de4               | add                 edi, dword ptr [ebp - 0x1c]
            //   8d8c0f53144402       | lea                 ecx, [edi + ecx + 0x2441453]
            //   c1c109               | rol                 ecx, 9
            //   03c8                 | add                 ecx, eax
            //   8bfe                 | mov                 edi, esi
            //   f7d7                 | not                 edi
            //   23f8                 | and                 edi, eax

        $sequence_1 = { e8???????? be00020000 56 8d8584faffff 6a00 50 }
            // n = 6, score = 200
            //   e8????????           |                     
            //   be00020000           | mov                 esi, 0x200
            //   56                   | push                esi
            //   8d8584faffff         | lea                 eax, [ebp - 0x57c]
            //   6a00                 | push                0
            //   50                   | push                eax

        $sequence_2 = { 8dbdfcefffff f3a5 be00080000 56 8d85fcdfffff 6a00 }
            // n = 6, score = 200
            //   8dbdfcefffff         | lea                 edi, [ebp - 0x1004]
            //   f3a5                 | rep movsd           dword ptr es:[edi], dword ptr [esi]
            //   be00080000           | mov                 esi, 0x800
            //   56                   | push                esi
            //   8d85fcdfffff         | lea                 eax, [ebp - 0x2004]
            //   6a00                 | push                0

        $sequence_3 = { 83c107 51 68???????? e8???????? 68???????? ff75f4 }
            // n = 6, score = 200
            //   83c107               | add                 ecx, 7
            //   51                   | push                ecx
            //   68????????           |                     
            //   e8????????           |                     
            //   68????????           |                     
            //   ff75f4               | push                dword ptr [ebp - 0xc]

        $sequence_4 = { b9???????? e8???????? 68???????? 6a0f 58 }
            // n = 5, score = 200
            //   b9????????           |                     
            //   e8????????           |                     
            //   68????????           |                     
            //   6a0f                 | push                0xf
            //   58                   | pop                 eax

        $sequence_5 = { 56 e8???????? 59 59 85c0 742f b9???????? }
            // n = 7, score = 200
            //   56                   | push                esi
            //   e8????????           |                     
            //   59                   | pop                 ecx
            //   59                   | pop                 ecx
            //   85c0                 | test                eax, eax
            //   742f                 | je                  0x31
            //   b9????????           |                     

        $sequence_6 = { 7e0d 33db 53 53 68???????? 6a03 }
            // n = 6, score = 200
            //   7e0d                 | jle                 0xf
            //   33db                 | xor                 ebx, ebx
            //   53                   | push                ebx
            //   53                   | push                ebx
            //   68????????           |                     
            //   6a03                 | push                3

        $sequence_7 = { 33c0 0fb7f0 8bc6 c1e610 ba???????? }
            // n = 5, score = 200
            //   33c0                 | xor                 eax, eax
            //   0fb7f0               | movzx               esi, ax
            //   8bc6                 | mov                 eax, esi
            //   c1e610               | shl                 esi, 0x10
            //   ba????????           |                     

        $sequence_8 = { e8???????? 8945f8 85c0 7905 83c8ff }
            // n = 5, score = 100
            //   e8????????           |                     
            //   8945f8               | mov                 dword ptr [ebp - 8], eax
            //   85c0                 | test                eax, eax
            //   7905                 | jns                 7
            //   83c8ff               | or                  eax, 0xffffffff

        $sequence_9 = { 59 7202 8b00 68???????? 50 8d85f0feffff 68???????? }
            // n = 7, score = 100
            //   59                   | pop                 ecx
            //   7202                 | jb                  4
            //   8b00                 | mov                 eax, dword ptr [eax]
            //   68????????           |                     
            //   50                   | push                eax
            //   8d85f0feffff         | lea                 eax, [ebp - 0x110]
            //   68????????           |                     

        $sequence_10 = { 83c40c 837d3c10 7303 8d4528 50 }
            // n = 5, score = 100
            //   83c40c               | add                 esp, 0xc
            //   837d3c10             | cmp                 dword ptr [ebp + 0x3c], 0x10
            //   7303                 | jae                 5
            //   8d4528               | lea                 eax, [ebp + 0x28]
            //   50                   | push                eax

        $sequence_11 = { 8db5a8fdffff c645fc02 e8???????? ffb51cfdffff ff15???????? }
            // n = 5, score = 100
            //   8db5a8fdffff         | lea                 esi, [ebp - 0x258]
            //   c645fc02             | mov                 byte ptr [ebp - 4], 2
            //   e8????????           |                     
            //   ffb51cfdffff         | push                dword ptr [ebp - 0x2e4]
            //   ff15????????         |                     

        $sequence_12 = { ffd7 8bf0 85f6 7f2b 8b93b0000000 33c0 }
            // n = 6, score = 100
            //   ffd7                 | call                edi
            //   8bf0                 | mov                 esi, eax
            //   85f6                 | test                esi, esi
            //   7f2b                 | jg                  0x2d
            //   8b93b0000000         | mov                 edx, dword ptr [ebx + 0xb0]
            //   33c0                 | xor                 eax, eax

        $sequence_13 = { 6a01 8db594feffff c645fc00 e8???????? 83ec1c }
            // n = 5, score = 100
            //   6a01                 | push                1
            //   8db594feffff         | lea                 esi, [ebp - 0x16c]
            //   c645fc00             | mov                 byte ptr [ebp - 4], 0
            //   e8????????           |                     
            //   83ec1c               | sub                 esp, 0x1c

        $sequence_14 = { ab ab ab 8d85f8eeffff }
            // n = 4, score = 100
            //   ab                   | stosd               dword ptr es:[edi], eax
            //   ab                   | stosd               dword ptr es:[edi], eax
            //   ab                   | stosd               dword ptr es:[edi], eax
            //   8d85f8eeffff         | lea                 eax, [ebp - 0x1108]

        $sequence_15 = { 68???????? e8???????? 68???????? ff15???????? 8b7508 c7465c20a24100 }
            // n = 6, score = 100
            //   68????????           |                     
            //   e8????????           |                     
            //   68????????           |                     
            //   ff15????????         |                     
            //   8b7508               | mov                 esi, dword ptr [ebp + 8]
            //   c7465c20a24100       | mov                 dword ptr [esi + 0x5c], 0x41a220

    condition:
        7 of them and filesize < 4599808
}