rule win_bleachgap_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.bleachgap."
        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.bleachgap"
        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 = { e8???????? 83c40c 85c0 0f8431020000 837e2000 8bbe74040000 8daf4c010000 }
            // n = 7, score = 100
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc
            //   85c0                 | test                eax, eax
            //   0f8431020000         | je                  0x237
            //   837e2000             | cmp                 dword ptr [esi + 0x20], 0
            //   8bbe74040000         | mov                 edi, dword ptr [esi + 0x474]
            //   8daf4c010000         | lea                 ebp, [edi + 0x14c]

        $sequence_1 = { c685affeffff27 c685b0feffff2e c685b1feffff2a c685b2feffff3b c685b3feffff3a c685b4feffff7f c685b5feffff7f }
            // n = 7, score = 100
            //   c685affeffff27       | mov                 byte ptr [ebp - 0x151], 0x27
            //   c685b0feffff2e       | mov                 byte ptr [ebp - 0x150], 0x2e
            //   c685b1feffff2a       | mov                 byte ptr [ebp - 0x14f], 0x2a
            //   c685b2feffff3b       | mov                 byte ptr [ebp - 0x14e], 0x3b
            //   c685b3feffff3a       | mov                 byte ptr [ebp - 0x14d], 0x3a
            //   c685b4feffff7f       | mov                 byte ptr [ebp - 0x14c], 0x7f
            //   c685b5feffff7f       | mov                 byte ptr [ebp - 0x14b], 0x7f

        $sequence_2 = { 8b407c 8b8860020000 ebd7 8b742410 83be7404000000 0f84e7f9ffff 8b467c }
            // n = 7, score = 100
            //   8b407c               | mov                 eax, dword ptr [eax + 0x7c]
            //   8b8860020000         | mov                 ecx, dword ptr [eax + 0x260]
            //   ebd7                 | jmp                 0xffffffd9
            //   8b742410             | mov                 esi, dword ptr [esp + 0x10]
            //   83be7404000000       | cmp                 dword ptr [esi + 0x474], 0
            //   0f84e7f9ffff         | je                  0xfffff9ed
            //   8b467c               | mov                 eax, dword ptr [esi + 0x7c]

        $sequence_3 = { 8b4d0c 74c6 8b45f8 807f0d00 7407 8b30 83c604 }
            // n = 7, score = 100
            //   8b4d0c               | mov                 ecx, dword ptr [ebp + 0xc]
            //   74c6                 | je                  0xffffffc8
            //   8b45f8               | mov                 eax, dword ptr [ebp - 8]
            //   807f0d00             | cmp                 byte ptr [edi + 0xd], 0
            //   7407                 | je                  9
            //   8b30                 | mov                 esi, dword ptr [eax]
            //   83c604               | add                 esi, 4

        $sequence_4 = { 8b4c2440 3bce 0f8cbd050000 8d046d02000000 3bc8 0f8cae050000 2bcd }
            // n = 7, score = 100
            //   8b4c2440             | mov                 ecx, dword ptr [esp + 0x40]
            //   3bce                 | cmp                 ecx, esi
            //   0f8cbd050000         | jl                  0x5c3
            //   8d046d02000000       | lea                 eax, [ebp*2 + 2]
            //   3bc8                 | cmp                 ecx, eax
            //   0f8cae050000         | jl                  0x5b4
            //   2bcd                 | sub                 ecx, ebp

        $sequence_5 = { 238798000000 33c8 894d18 8b8f9c000000 8b451c 23ce 57 }
            // n = 7, score = 100
            //   238798000000         | and                 eax, dword ptr [edi + 0x98]
            //   33c8                 | xor                 ecx, eax
            //   894d18               | mov                 dword ptr [ebp + 0x18], ecx
            //   8b8f9c000000         | mov                 ecx, dword ptr [edi + 0x9c]
            //   8b451c               | mov                 eax, dword ptr [ebp + 0x1c]
            //   23ce                 | and                 ecx, esi
            //   57                   | push                edi

        $sequence_6 = { 8bd6 03d1 33c0 89542414 8bfe 2bd6 7411 }
            // n = 7, score = 100
            //   8bd6                 | mov                 edx, esi
            //   03d1                 | add                 edx, ecx
            //   33c0                 | xor                 eax, eax
            //   89542414             | mov                 dword ptr [esp + 0x14], edx
            //   8bfe                 | mov                 edi, esi
            //   2bd6                 | sub                 edx, esi
            //   7411                 | je                  0x13

        $sequence_7 = { 5e c3 68b6040000 68???????? 6a44 686b020000 6a50 }
            // n = 7, score = 100
            //   5e                   | pop                 esi
            //   c3                   | ret                 
            //   68b6040000           | push                0x4b6
            //   68????????           |                     
            //   6a44                 | push                0x44
            //   686b020000           | push                0x26b
            //   6a50                 | push                0x50

        $sequence_8 = { e8???????? 8b6c2428 83c410 894500 85c0 0f8411010000 8b4604 }
            // n = 7, score = 100
            //   e8????????           |                     
            //   8b6c2428             | mov                 ebp, dword ptr [esp + 0x28]
            //   83c410               | add                 esp, 0x10
            //   894500               | mov                 dword ptr [ebp], eax
            //   85c0                 | test                eax, eax
            //   0f8411010000         | je                  0x117
            //   8b4604               | mov                 eax, dword ptr [esi + 4]

        $sequence_9 = { c645fc02 8b8d68ffffff 83f910 722f 8b9554ffffff 41 8bc2 }
            // n = 7, score = 100
            //   c645fc02             | mov                 byte ptr [ebp - 4], 2
            //   8b8d68ffffff         | mov                 ecx, dword ptr [ebp - 0x98]
            //   83f910               | cmp                 ecx, 0x10
            //   722f                 | jb                  0x31
            //   8b9554ffffff         | mov                 edx, dword ptr [ebp - 0xac]
            //   41                   | inc                 ecx
            //   8bc2                 | mov                 eax, edx

    condition:
        7 of them and filesize < 4538368
}