rule win_cryptoshield_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.cryptoshield."
        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.cryptoshield"
        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 = { 83fe03 7413 83fe02 740e 83fe04 }
            // n = 5, score = 300
            //   83fe03               | cmp                 esi, 3
            //   7413                 | je                  0x15
            //   83fe02               | cmp                 esi, 2
            //   740e                 | je                  0x10
            //   83fe04               | cmp                 esi, 4

        $sequence_1 = { 83f801 7409 83f802 0f85a5000000 be02000000 8bc6 5e }
            // n = 7, score = 300
            //   83f801               | cmp                 eax, 1
            //   7409                 | je                  0xb
            //   83f802               | cmp                 eax, 2
            //   0f85a5000000         | jne                 0xab
            //   be02000000           | mov                 esi, 2
            //   8bc6                 | mov                 eax, esi
            //   5e                   | pop                 esi

        $sequence_2 = { ff15???????? 85c0 0f8487000000 8b4508 }
            // n = 4, score = 300
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax
            //   0f8487000000         | je                  0x8d
            //   8b4508               | mov                 eax, dword ptr [ebp + 8]

        $sequence_3 = { 66833800 740c 0fb77202 83c202 6685f6 }
            // n = 5, score = 300
            //   66833800             | cmp                 word ptr [eax], 0
            //   740c                 | je                  0xe
            //   0fb77202             | movzx               esi, word ptr [edx + 2]
            //   83c202               | add                 edx, 2
            //   6685f6               | test                si, si

        $sequence_4 = { 8d85b0fbffff 50 c785ccfbffff00000000 ff15???????? 85c0 752f ff15???????? }
            // n = 7, score = 300
            //   8d85b0fbffff         | lea                 eax, [ebp - 0x450]
            //   50                   | push                eax
            //   c785ccfbffff00000000     | mov    dword ptr [ebp - 0x434], 0
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax
            //   752f                 | jne                 0x31
            //   ff15????????         |                     

        $sequence_5 = { 68???????? 50 ffd6 83c40c 8d45f0 6a00 }
            // n = 6, score = 300
            //   68????????           |                     
            //   50                   | push                eax
            //   ffd6                 | call                esi
            //   83c40c               | add                 esp, 0xc
            //   8d45f0               | lea                 eax, [ebp - 0x10]
            //   6a00                 | push                0

        $sequence_6 = { 0f84a6000000 8d45fc 50 6a01 ff75f8 6810660000 }
            // n = 6, score = 300
            //   0f84a6000000         | je                  0xac
            //   8d45fc               | lea                 eax, [ebp - 4]
            //   50                   | push                eax
            //   6a01                 | push                1
            //   ff75f8               | push                dword ptr [ebp - 8]
            //   6810660000           | push                0x6610

        $sequence_7 = { 33c0 8d95f4fdffff 6685c9 7417 0fb7c9 90 c1c007 }
            // n = 7, score = 300
            //   33c0                 | xor                 eax, eax
            //   8d95f4fdffff         | lea                 edx, [ebp - 0x20c]
            //   6685c9               | test                cx, cx
            //   7417                 | je                  0x19
            //   0fb7c9               | movzx               ecx, cx
            //   90                   | nop                 
            //   c1c007               | rol                 eax, 7

        $sequence_8 = { be02000000 8bc6 5e 8b4dfc 33cd }
            // n = 5, score = 300
            //   be02000000           | mov                 esi, 2
            //   8bc6                 | mov                 eax, esi
            //   5e                   | pop                 esi
            //   8b4dfc               | mov                 ecx, dword ptr [ebp - 4]
            //   33cd                 | xor                 ecx, ebp

        $sequence_9 = { 8d4900 0fb706 8bd6 6685c0 743b 8bf0 }
            // n = 6, score = 300
            //   8d4900               | lea                 ecx, [ecx]
            //   0fb706               | movzx               eax, word ptr [esi]
            //   8bd6                 | mov                 edx, esi
            //   6685c0               | test                ax, ax
            //   743b                 | je                  0x3d
            //   8bf0                 | mov                 esi, eax

    condition:
        7 of them and filesize < 131072
}