rule win_kasperagent_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.kasperagent."
        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.kasperagent"
        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 = { c645fc1d e8???????? 33c9 85c0 0f95c1 85c9 750a }
            // n = 7, score = 200
            //   c645fc1d             | mov                 byte ptr [ebp - 4], 0x1d
            //   e8????????           |                     
            //   33c9                 | xor                 ecx, ecx
            //   85c0                 | test                eax, eax
            //   0f95c1               | setne               cl
            //   85c9                 | test                ecx, ecx
            //   750a                 | jne                 0xc

        $sequence_1 = { 8b08 8b11 50 8b4204 ffd0 8d4db0 8975fc }
            // n = 7, score = 200
            //   8b08                 | mov                 ecx, dword ptr [eax]
            //   8b11                 | mov                 edx, dword ptr [ecx]
            //   50                   | push                eax
            //   8b4204               | mov                 eax, dword ptr [edx + 4]
            //   ffd0                 | call                eax
            //   8d4db0               | lea                 ecx, [ebp - 0x50]
            //   8975fc               | mov                 dword ptr [ebp - 4], esi

        $sequence_2 = { 89542408 3bc2 734d 53 }
            // n = 4, score = 200
            //   89542408             | mov                 dword ptr [esp + 8], edx
            //   3bc2                 | cmp                 eax, edx
            //   734d                 | jae                 0x4f
            //   53                   | push                ebx

        $sequence_3 = { 33c9 85c0 0f95c1 85c9 7517 }
            // n = 5, score = 200
            //   33c9                 | xor                 ecx, ecx
            //   85c0                 | test                eax, eax
            //   0f95c1               | setne               cl
            //   85c9                 | test                ecx, ecx
            //   7517                 | jne                 0x19

        $sequence_4 = { 663b542420 7428 8bd3 2bd0 d1fa }
            // n = 5, score = 200
            //   663b542420           | cmp                 dx, word ptr [esp + 0x20]
            //   7428                 | je                  0x2a
            //   8bd3                 | mov                 edx, ebx
            //   2bd0                 | sub                 edx, eax
            //   d1fa                 | sar                 edx, 1

        $sequence_5 = { 7cda 33f6 eb02 8bf0 834dfcff 8d8dd0fdffff }
            // n = 6, score = 200
            //   7cda                 | jl                  0xffffffdc
            //   33f6                 | xor                 esi, esi
            //   eb02                 | jmp                 4
            //   8bf0                 | mov                 esi, eax
            //   834dfcff             | or                  dword ptr [ebp - 4], 0xffffffff
            //   8d8dd0fdffff         | lea                 ecx, [ebp - 0x230]

        $sequence_6 = { 2bc1 0bd0 7d0a 51 8b4c242c }
            // n = 5, score = 200
            //   2bc1                 | sub                 eax, ecx
            //   0bd0                 | or                  edx, eax
            //   7d0a                 | jge                 0xc
            //   51                   | push                ecx
            //   8b4c242c             | mov                 ecx, dword ptr [esp + 0x2c]

        $sequence_7 = { 8b5500 33c0 66890472 8b442414 5f }
            // n = 5, score = 200
            //   8b5500               | mov                 edx, dword ptr [ebp]
            //   33c0                 | xor                 eax, eax
            //   66890472             | mov                 word ptr [edx + esi*2], ax
            //   8b442414             | mov                 eax, dword ptr [esp + 0x14]
            //   5f                   | pop                 edi

        $sequence_8 = { 668b5602 663b542432 7537 668b4606 663b442436 752c }
            // n = 6, score = 200
            //   668b5602             | mov                 dx, word ptr [esi + 2]
            //   663b542432           | cmp                 dx, word ptr [esp + 0x32]
            //   7537                 | jne                 0x39
            //   668b4606             | mov                 ax, word ptr [esi + 6]
            //   663b442436           | cmp                 ax, word ptr [esp + 0x36]
            //   752c                 | jne                 0x2e

        $sequence_9 = { 85c0 740e 33c0 894708 }
            // n = 4, score = 200
            //   85c0                 | test                eax, eax
            //   740e                 | je                  0x10
            //   33c0                 | xor                 eax, eax
            //   894708               | mov                 dword ptr [edi + 8], eax

    condition:
        7 of them and filesize < 1605632
}