rule win_klrd_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2023-03-28"
        version = "1"
        description = "Detects win.klrd."
        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.klrd"
        malpedia_rule_date = "20230328"
        malpedia_hash = "9d2d75cef573c1c2d861f5197df8f563b05a305d"
        malpedia_version = "20230407"
        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 = { 80bdacfcffff20 7432 eb57 68???????? e8???????? 59 e9???????? }
            // n = 7, score = 100
            //   80bdacfcffff20       | cmp                 byte ptr [ebp - 0x354], 0x20
            //   7432                 | je                  0x34
            //   eb57                 | jmp                 0x59
            //   68????????           |                     
            //   e8????????           |                     
            //   59                   | pop                 ecx
            //   e9????????           |                     

        $sequence_1 = { ab c685c0fdffff00 68ff000000 6a00 8d85c1fdffff 50 e8???????? }
            // n = 7, score = 100
            //   ab                   | stosd               dword ptr es:[edi], eax
            //   c685c0fdffff00       | mov                 byte ptr [ebp - 0x240], 0
            //   68ff000000           | push                0xff
            //   6a00                 | push                0
            //   8d85c1fdffff         | lea                 eax, [ebp - 0x23f]
            //   50                   | push                eax
            //   e8????????           |                     

        $sequence_2 = { 8d85fcefffff 50 57 ff15???????? 57 }
            // n = 5, score = 100
            //   8d85fcefffff         | lea                 eax, [ebp - 0x1004]
            //   50                   | push                eax
            //   57                   | push                edi
            //   ff15????????         |                     
            //   57                   | push                edi

        $sequence_3 = { 8985d4feffff 83bdd4feffff00 7502 eb26 0fb785c4feffff }
            // n = 5, score = 100
            //   8985d4feffff         | mov                 dword ptr [ebp - 0x12c], eax
            //   83bdd4feffff00       | cmp                 dword ptr [ebp - 0x12c], 0
            //   7502                 | jne                 4
            //   eb26                 | jmp                 0x28
            //   0fb785c4feffff       | movzx               eax, word ptr [ebp - 0x13c]

        $sequence_4 = { 83c40c 53 ff15???????? 3bc3 7554 6804010000 8d85fcfeffff }
            // n = 7, score = 100
            //   83c40c               | add                 esp, 0xc
            //   53                   | push                ebx
            //   ff15????????         |                     
            //   3bc3                 | cmp                 eax, ebx
            //   7554                 | jne                 0x56
            //   6804010000           | push                0x104
            //   8d85fcfeffff         | lea                 eax, [ebp - 0x104]

        $sequence_5 = { 59 8d85fcfeffff 50 ff15???????? 3bc3 }
            // n = 5, score = 100
            //   59                   | pop                 ecx
            //   8d85fcfeffff         | lea                 eax, [ebp - 0x104]
            //   50                   | push                eax
            //   ff15????????         |                     
            //   3bc3                 | cmp                 eax, ebx

        $sequence_6 = { 8d85c1fdffff 50 e8???????? 83c40c 83a5b0fcffff00 }
            // n = 5, score = 100
            //   8d85c1fdffff         | lea                 eax, [ebp - 0x23f]
            //   50                   | push                eax
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc
            //   83a5b0fcffff00       | and                 dword ptr [ebp - 0x350], 0

        $sequence_7 = { 56 57 83a5ccfeffff00 83a5c8feffff00 83a5d0feffff00 83a5d4feffff00 c685b8fcffff00 }
            // n = 7, score = 100
            //   56                   | push                esi
            //   57                   | push                edi
            //   83a5ccfeffff00       | and                 dword ptr [ebp - 0x134], 0
            //   83a5c8feffff00       | and                 dword ptr [ebp - 0x138], 0
            //   83a5d0feffff00       | and                 dword ptr [ebp - 0x130], 0
            //   83a5d4feffff00       | and                 dword ptr [ebp - 0x12c], 0
            //   c685b8fcffff00       | mov                 byte ptr [ebp - 0x348], 0

        $sequence_8 = { 740d 817d0c00010000 0f85a6020000 8b7510 6a05 59 8d7dec }
            // n = 7, score = 100
            //   740d                 | je                  0xf
            //   817d0c00010000       | cmp                 dword ptr [ebp + 0xc], 0x100
            //   0f85a6020000         | jne                 0x2ac
            //   8b7510               | mov                 esi, dword ptr [ebp + 0x10]
            //   6a05                 | push                5
            //   59                   | pop                 ecx
            //   8d7dec               | lea                 edi, [ebp - 0x14]

        $sequence_9 = { 8d85e8feffff 50 ffb5b0fcffff ff15???????? 85c0 7515 }
            // n = 6, score = 100
            //   8d85e8feffff         | lea                 eax, [ebp - 0x118]
            //   50                   | push                eax
            //   ffb5b0fcffff         | push                dword ptr [ebp - 0x350]
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax
            //   7515                 | jne                 0x17

    condition:
        7 of them and filesize < 40960
}