rule win_bid_ransomware_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.bid_ransomware."
        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.bid_ransomware"
        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 = { 6a00 e8???????? ff75a8 e8???????? }
            // n = 4, score = 200
            //   6a00                 | push                0
            //   e8????????           |                     
            //   ff75a8               | push                dword ptr [ebp - 0x58]
            //   e8????????           |                     

        $sequence_1 = { 6800400000 6a40 e8???????? 0bc0 750c 68c8000000 }
            // n = 6, score = 200
            //   6800400000           | push                0x4000
            //   6a40                 | push                0x40
            //   e8????????           |                     
            //   0bc0                 | or                  eax, eax
            //   750c                 | jne                 0xe
            //   68c8000000           | push                0xc8

        $sequence_2 = { e8???????? c745942c000000 8d4594 50 ff75a8 6a00 6a08 }
            // n = 7, score = 200
            //   e8????????           |                     
            //   c745942c000000       | mov                 dword ptr [ebp - 0x6c], 0x2c
            //   8d4594               | lea                 eax, [ebp - 0x6c]
            //   50                   | push                eax
            //   ff75a8               | push                dword ptr [ebp - 0x58]
            //   6a00                 | push                0
            //   6a08                 | push                8

        $sequence_3 = { 757b ff05???????? c705????????20202020 68???????? ff35???????? e8???????? }
            // n = 6, score = 200
            //   757b                 | jne                 0x7d
            //   ff05????????         |                     
            //   c705????????20202020     |     
            //   68????????           |                     
            //   ff35????????         |                     
            //   e8????????           |                     

        $sequence_4 = { ff75b0 e8???????? 6a04 ff75a8 6a04 6a00 }
            // n = 6, score = 200
            //   ff75b0               | push                dword ptr [ebp - 0x50]
            //   e8????????           |                     
            //   6a04                 | push                4
            //   ff75a8               | push                dword ptr [ebp - 0x58]
            //   6a04                 | push                4
            //   6a00                 | push                0

        $sequence_5 = { 68dc050000 ff75a8 68???????? e8???????? 6a00 }
            // n = 5, score = 200
            //   68dc050000           | push                0x5dc
            //   ff75a8               | push                dword ptr [ebp - 0x58]
            //   68????????           |                     
            //   e8????????           |                     
            //   6a00                 | push                0

        $sequence_6 = { ff75a8 6a03 6a00 ff7590 ff75b0 e8???????? ff75b0 }
            // n = 7, score = 200
            //   ff75a8               | push                dword ptr [ebp - 0x58]
            //   6a03                 | push                3
            //   6a00                 | push                0
            //   ff7590               | push                dword ptr [ebp - 0x70]
            //   ff75b0               | push                dword ptr [ebp - 0x50]
            //   e8????????           |                     
            //   ff75b0               | push                dword ptr [ebp - 0x50]

        $sequence_7 = { d1e0 83e806 c6043000 8d85d8fdffff }
            // n = 4, score = 200
            //   d1e0                 | shl                 eax, 1
            //   83e806               | sub                 eax, 6
            //   c6043000             | mov                 byte ptr [eax + esi], 0
            //   8d85d8fdffff         | lea                 eax, [ebp - 0x228]

        $sequence_8 = { c1e005 0345e8 83780c01 740c 6a00 8d00 }
            // n = 6, score = 200
            //   c1e005               | shl                 eax, 5
            //   0345e8               | add                 eax, dword ptr [ebp - 0x18]
            //   83780c01             | cmp                 dword ptr [eax + 0xc], 1
            //   740c                 | je                  0xe
            //   6a00                 | push                0
            //   8d00                 | lea                 eax, [eax]

        $sequence_9 = { ff75f0 6a40 e8???????? 0bc0 750c 68c8000000 e8???????? }
            // n = 7, score = 200
            //   ff75f0               | push                dword ptr [ebp - 0x10]
            //   6a40                 | push                0x40
            //   e8????????           |                     
            //   0bc0                 | or                  eax, eax
            //   750c                 | jne                 0xe
            //   68c8000000           | push                0xc8
            //   e8????????           |                     

    condition:
        7 of them and filesize < 57344
}