rule win_webc2_cson_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2023-03-28"
        version = "1"
        description = "Detects win.webc2_cson."
        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.webc2_cson"
        malpedia_rule_date = "20230328"
        malpedia_hash = "9d2d75cef573c1c2d861f5197df8f563b05a305d"
        malpedia_version = "20230407"
        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 = { c745f420000000 ffd6 8d8540ffffff 50 ff15???????? 8bf0 8d4601 }
            // n = 7, score = 100
            //   c745f420000000       | mov                 dword ptr [ebp - 0xc], 0x20
            //   ffd6                 | call                esi
            //   8d8540ffffff         | lea                 eax, [ebp - 0xc0]
            //   50                   | push                eax
            //   ff15????????         |                     
            //   8bf0                 | mov                 esi, eax
            //   8d4601               | lea                 eax, [esi + 1]

        $sequence_1 = { 66ab aa 8d85c0d6ffff 50 e8???????? 85c0 59 }
            // n = 7, score = 100
            //   66ab                 | stosw               word ptr es:[edi], ax
            //   aa                   | stosb               byte ptr es:[edi], al
            //   8d85c0d6ffff         | lea                 eax, [ebp - 0x2940]
            //   50                   | push                eax
            //   e8????????           |                     
            //   85c0                 | test                eax, eax
            //   59                   | pop                 ecx

        $sequence_2 = { 48 0f849c010000 83e803 0f8473010000 }
            // n = 4, score = 100
            //   48                   | dec                 eax
            //   0f849c010000         | je                  0x1a2
            //   83e803               | sub                 eax, 3
            //   0f8473010000         | je                  0x179

        $sequence_3 = { 6a1e 8db5f6feffff 59 8dbd70ffffff f3a5 6a04 8d8570ffffff }
            // n = 7, score = 100
            //   6a1e                 | push                0x1e
            //   8db5f6feffff         | lea                 esi, [ebp - 0x10a]
            //   59                   | pop                 ecx
            //   8dbd70ffffff         | lea                 edi, [ebp - 0x90]
            //   f3a5                 | rep movsd           dword ptr es:[edi], dword ptr [esi]
            //   6a04                 | push                4
            //   8d8570ffffff         | lea                 eax, [ebp - 0x90]

        $sequence_4 = { 7515 53 ffd6 55 ffd6 57 }
            // n = 6, score = 100
            //   7515                 | jne                 0x17
            //   53                   | push                ebx
            //   ffd6                 | call                esi
            //   55                   | push                ebp
            //   ffd6                 | call                esi
            //   57                   | push                edi

        $sequence_5 = { 56 c785d8feffff28010000 e8???????? 85c0 744d 8d85d8feffff }
            // n = 6, score = 100
            //   56                   | push                esi
            //   c785d8feffff28010000     | mov    dword ptr [ebp - 0x128], 0x128
            //   e8????????           |                     
            //   85c0                 | test                eax, eax
            //   744d                 | je                  0x4f
            //   8d85d8feffff         | lea                 eax, [ebp - 0x128]

        $sequence_6 = { ff15???????? 8bd8 85db 7512 55 ffd6 }
            // n = 6, score = 100
            //   ff15????????         |                     
            //   8bd8                 | mov                 ebx, eax
            //   85db                 | test                ebx, ebx
            //   7512                 | jne                 0x14
            //   55                   | push                ebp
            //   ffd6                 | call                esi

        $sequence_7 = { 81ec54030000 53 56 8b35???????? 57 33db 68???????? }
            // n = 7, score = 100
            //   81ec54030000         | sub                 esp, 0x354
            //   53                   | push                ebx
            //   56                   | push                esi
            //   8b35????????         |                     
            //   57                   | push                edi
            //   33db                 | xor                 ebx, ebx
            //   68????????           |                     

        $sequence_8 = { c745c43c000000 c745c840000000 c745d078434000 8945d8 ffd7 8b35???????? }
            // n = 6, score = 100
            //   c745c43c000000       | mov                 dword ptr [ebp - 0x3c], 0x3c
            //   c745c840000000       | mov                 dword ptr [ebp - 0x38], 0x40
            //   c745d078434000       | mov                 dword ptr [ebp - 0x30], 0x404378
            //   8945d8               | mov                 dword ptr [ebp - 0x28], eax
            //   ffd7                 | call                edi
            //   8b35????????         |                     

        $sequence_9 = { 6800020000 ff15???????? 8d85acfcffff 50 e8???????? 80bc05abfcffff5c 59 }
            // n = 7, score = 100
            //   6800020000           | push                0x200
            //   ff15????????         |                     
            //   8d85acfcffff         | lea                 eax, [ebp - 0x354]
            //   50                   | push                eax
            //   e8????????           |                     
            //   80bc05abfcffff5c     | cmp                 byte ptr [ebp + eax - 0x355], 0x5c
            //   59                   | pop                 ecx

    condition:
        7 of them and filesize < 98304
}