rule win_fobber_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.fobber."
        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.fobber"
        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 = { 89e5 57 51 8b7d08 }
            // n = 4, score = 1100
            //   89e5                 | mov                 ebp, esp
            //   57                   | push                edi
            //   51                   | push                ecx
            //   8b7d08               | mov                 edi, dword ptr [ebp + 8]

        $sequence_1 = { 760e 8d0431 39f8 7607 49 01cf 01ce }
            // n = 7, score = 1100
            // 
            //   8d0431               | lea                 eax, [ecx + esi]
            //   39f8                 | cmp                 eax, edi
            //   7607                 | jbe                 9
            //   49                   | dec                 ecx
            //   01cf                 | add                 edi, ecx
            //   01ce                 | add                 esi, ecx

        $sequence_2 = { 31c0 50 50 ff750c ff7508 }
            // n = 5, score = 1100
            //   31c0                 | xor                 eax, eax
            //   50                   | push                eax
            //   50                   | push                eax
            //   ff750c               | push                dword ptr [ebp + 0xc]
            //   ff7508               | push                dword ptr [ebp + 8]

        $sequence_3 = { 55 89e5 51 8b4510 8b5508 8b4d0c }
            // n = 6, score = 1100
            //   55                   | push                ebp
            //   89e5                 | mov                 ebp, esp
            //   51                   | push                ecx
            //   8b4510               | mov                 eax, dword ptr [ebp + 0x10]
            //   8b5508               | mov                 edx, dword ptr [ebp + 8]
            //   8b4d0c               | mov                 ecx, dword ptr [ebp + 0xc]

        $sequence_4 = { 8b7d08 57 e8???????? 85c0 740f 89c1 }
            // n = 6, score = 1100
            //   8b7d08               | mov                 edi, dword ptr [ebp + 8]
            //   57                   | push                edi
            //   e8????????           |                     
            //   85c0                 | test                eax, eax
            //   740f                 | je                  0x11
            //   89c1                 | mov                 ecx, eax

        $sequence_5 = { 8b7d08 8b750c 8b4d10 39f7 760e }
            // n = 5, score = 1100
            //   8b7d08               | mov                 edi, dword ptr [ebp + 8]
            //   8b750c               | mov                 esi, dword ptr [ebp + 0xc]
            //   8b4d10               | mov                 ecx, dword ptr [ebp + 0x10]
            //   39f7                 | cmp                 edi, esi
            //   760e                 | jbe                 0x10

        $sequence_6 = { ff750c 6800300000 ff7508 6a00 }
            // n = 4, score = 1100
            //   ff750c               | push                dword ptr [ebp + 0xc]
            //   6800300000           | push                0x3000
            //   ff7508               | push                dword ptr [ebp + 8]
            //   6a00                 | push                0

        $sequence_7 = { 660fc146f9 6685c0 7515 0fb646f8 50 0fb746f6 }
            // n = 6, score = 1100
            //   660fc146f9           | xadd                word ptr [esi - 7], ax
            //   6685c0               | test                ax, ax
            //   7515                 | jne                 0x17
            //   0fb646f8             | movzx               eax, byte ptr [esi - 8]
            //   50                   | push                eax
            //   0fb746f6             | movzx               eax, word ptr [esi - 0xa]

        $sequence_8 = { a4 06 4f 96 }
            // n = 4, score = 100
            //   a4                   | movsb               byte ptr es:[edi], byte ptr [esi]
            //   06                   | push                es
            //   4f                   | dec                 edi
            //   96                   | xchg                eax, esi

        $sequence_9 = { 81e8ca080000 81e8e1970000 81e83e6e0100 e9???????? 81c6b8690000 }
            // n = 5, score = 100
            //   81e8ca080000         | sub                 eax, 0x8ca
            //   81e8e1970000         | sub                 eax, 0x97e1
            //   81e83e6e0100         | sub                 eax, 0x16e3e
            //   e9????????           |                     
            //   81c6b8690000         | add                 esi, 0x69b8

        $sequence_10 = { 3a918d84a72f bf9cd7e94d 09d9 2817 3f }
            // n = 5, score = 100
            //   3a918d84a72f         | cmp                 dl, byte ptr [ecx + 0x2fa7848d]
            //   bf9cd7e94d           | mov                 edi, 0x4de9d79c
            //   09d9                 | or                  ecx, ebx
            //   2817                 | sub                 byte ptr [edi], dl
            //   3f                   | aas                 

        $sequence_11 = { 48 5e fa df9c6182a5b1b2 e8???????? }
            // n = 5, score = 100
            //   48                   | dec                 eax
            //   5e                   | pop                 esi
            //   fa                   | cli                 
            //   df9c6182a5b1b2       | fistp               word ptr [ecx - 0x4d4e5a7e]
            //   e8????????           |                     

        $sequence_12 = { 0f85c44c0100 8b4510 8945f0 663918 7419 83c002 }
            // n = 6, score = 100
            //   0f85c44c0100         | jne                 0x14cca
            //   8b4510               | mov                 eax, dword ptr [ebp + 0x10]
            //   8945f0               | mov                 dword ptr [ebp - 0x10], eax
            //   663918               | cmp                 word ptr [eax], bx
            //   7419                 | je                  0x1b
            //   83c002               | add                 eax, 2

        $sequence_13 = { 96 f0f266a2???????? 857f47 94 6960cf0267b974 }
            // n = 5, score = 100
            //   96                   | xchg                eax, esi
            //   f0f266a2????????     |                     
            //   857f47               | test                dword ptr [edi + 0x47], edi
            //   94                   | xchg                eax, esp
            //   6960cf0267b974       | imul                esp, dword ptr [eax - 0x31], 0x74b96702

        $sequence_14 = { 81eccd210000 81c4455a0000 81c42c090000 81c4ab1e0000 81ec6f790000 81ec956ffeff 81c45a1b0000 }
            // n = 7, score = 100
            //   81eccd210000         | sub                 esp, 0x21cd
            //   81c4455a0000         | add                 esp, 0x5a45
            //   81c42c090000         | add                 esp, 0x92c
            //   81c4ab1e0000         | add                 esp, 0x1eab
            //   81ec6f790000         | sub                 esp, 0x796f
            //   81ec956ffeff         | sub                 esp, 0xfffe6f95
            //   81c45a1b0000         | add                 esp, 0x1b5a

        $sequence_15 = { 59 663908 0f842b150100 ff07 }
            // n = 4, score = 100
            //   59                   | pop                 ecx
            //   663908               | cmp                 word ptr [eax], cx
            //   0f842b150100         | je                  0x11531
            //   ff07                 | inc                 dword ptr [edi]

    condition:
        7 of them and filesize < 188416
}