rule win_startpage_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.startpage."
        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.startpage"
        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 = { e9???????? bb09000280 eb19 bb05400080 eb12 8b4d8c 8b45a4 }
            // n = 7, score = 200
            //   e9????????           |                     
            //   bb09000280           | mov                 ebx, 0x80020009
            //   eb19                 | jmp                 0x1b
            //   bb05400080           | mov                 ebx, 0x80004005
            //   eb12                 | jmp                 0x14
            //   8b4d8c               | mov                 ecx, dword ptr [ebp - 0x74]
            //   8b45a4               | mov                 eax, dword ptr [ebp - 0x5c]

        $sequence_1 = { 7246 8b4dd8 40 32d2 0f8545010000 3d00100000 722a }
            // n = 7, score = 200
            //   7246                 | jb                  0x48
            //   8b4dd8               | mov                 ecx, dword ptr [ebp - 0x28]
            //   40                   | inc                 eax
            //   32d2                 | xor                 dl, dl
            //   0f8545010000         | jne                 0x14b
            //   3d00100000           | cmp                 eax, 0x1000
            //   722a                 | jb                  0x2c

        $sequence_2 = { 33c0 e8???????? c21000 55 8bec 8b5510 53 }
            // n = 7, score = 200
            //   33c0                 | xor                 eax, eax
            //   e8????????           |                     
            //   c21000               | ret                 0x10
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp
            //   8b5510               | mov                 edx, dword ptr [ebp + 0x10]
            //   53                   | push                ebx

        $sequence_3 = { ff5008 50 8d4e08 e8???????? 85c0 7504 33c9 }
            // n = 7, score = 200
            //   ff5008               | call                dword ptr [eax + 8]
            //   50                   | push                eax
            //   8d4e08               | lea                 ecx, [esi + 8]
            //   e8????????           |                     
            //   85c0                 | test                eax, eax
            //   7504                 | jne                 6
            //   33c9                 | xor                 ecx, ecx

        $sequence_4 = { e8???????? 59 e8???????? c20c00 6844020000 b8???????? }
            // n = 6, score = 200
            //   e8????????           |                     
            //   59                   | pop                 ecx
            //   e8????????           |                     
            //   c20c00               | ret                 0xc
            //   6844020000           | push                0x244
            //   b8????????           |                     

        $sequence_5 = { 42 83fa04 75f2 33c0 83f924 0f44c8 }
            // n = 6, score = 200
            //   42                   | inc                 edx
            //   83fa04               | cmp                 edx, 4
            //   75f2                 | jne                 0xfffffff4
            //   33c0                 | xor                 eax, eax
            //   83f924               | cmp                 ecx, 0x24
            //   0f44c8               | cmove               ecx, eax

        $sequence_6 = { 7406 8b06 56 ff5004 8b7d08 8bc6 6a02 }
            // n = 7, score = 200
            //   7406                 | je                  8
            //   8b06                 | mov                 eax, dword ptr [esi]
            //   56                   | push                esi
            //   ff5004               | call                dword ptr [eax + 4]
            //   8b7d08               | mov                 edi, dword ptr [ebp + 8]
            //   8bc6                 | mov                 eax, esi
            //   6a02                 | push                2

        $sequence_7 = { c745e000000000 c745e40f000000 c645d000 c745fc00000000 8d4dd0 f30f7e00 8b4008 }
            // n = 7, score = 200
            //   c745e000000000       | mov                 dword ptr [ebp - 0x20], 0
            //   c745e40f000000       | mov                 dword ptr [ebp - 0x1c], 0xf
            //   c645d000             | mov                 byte ptr [ebp - 0x30], 0
            //   c745fc00000000       | mov                 dword ptr [ebp - 4], 0
            //   8d4dd0               | lea                 ecx, [ebp - 0x30]
            //   f30f7e00             | movq                xmm0, qword ptr [eax]
            //   8b4008               | mov                 eax, dword ptr [eax + 8]

        $sequence_8 = { 8b85d8feffff 8bf8 83e710 89bde0feffff 0f84b7000000 8b4b2c 83e910 }
            // n = 7, score = 200
            //   8b85d8feffff         | mov                 eax, dword ptr [ebp - 0x128]
            //   8bf8                 | mov                 edi, eax
            //   83e710               | and                 edi, 0x10
            //   89bde0feffff         | mov                 dword ptr [ebp - 0x120], edi
            //   0f84b7000000         | je                  0xbd
            //   8b4b2c               | mov                 ecx, dword ptr [ebx + 0x2c]
            //   83e910               | sub                 ecx, 0x10

        $sequence_9 = { 8d8de0feffff e8???????? 59 c645fc0a 8d8ddcfeffff ff36 ff30 }
            // n = 7, score = 200
            //   8d8de0feffff         | lea                 ecx, [ebp - 0x120]
            //   e8????????           |                     
            //   59                   | pop                 ecx
            //   c645fc0a             | mov                 byte ptr [ebp - 4], 0xa
            //   8d8ddcfeffff         | lea                 ecx, [ebp - 0x124]
            //   ff36                 | push                dword ptr [esi]
            //   ff30                 | push                dword ptr [eax]

    condition:
        7 of them and filesize < 2277376
}