rule win_evilgrab_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2023-03-28"
        version = "1"
        description = "Detects win.evilgrab."
        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.evilgrab"
        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 = { 83e103 f3a4 66c705????????901f c705????????00000000 bf???????? 83c9ff 33c0 }
            // n = 7, score = 200
            //   83e103               | and                 ecx, 3
            //   f3a4                 | rep movsb           byte ptr es:[edi], byte ptr [esi]
            //   66c705????????901f     |     
            //   c705????????00000000     |     
            //   bf????????           |                     
            //   83c9ff               | or                  ecx, 0xffffffff
            //   33c0                 | xor                 eax, eax

        $sequence_1 = { 83e103 53 f3a4 ff15???????? 85c0 7416 5f }
            // n = 7, score = 200
            //   83e103               | and                 ecx, 3
            //   53                   | push                ebx
            //   f3a4                 | rep movsb           byte ptr es:[edi], byte ptr [esi]
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax
            //   7416                 | je                  0x18
            //   5f                   | pop                 edi

        $sequence_2 = { 752a 6a2a 68???????? 8d8500f6ffff 50 ff15???????? 83c40c }
            // n = 7, score = 200
            //   752a                 | jne                 0x2c
            //   6a2a                 | push                0x2a
            //   68????????           |                     
            //   8d8500f6ffff         | lea                 eax, [ebp - 0xa00]
            //   50                   | push                eax
            //   ff15????????         |                     
            //   83c40c               | add                 esp, 0xc

        $sequence_3 = { 0f8497010000 8d9515ebffff 8995b0aeffff 68???????? 8d8515ebffff 50 ff15???????? }
            // n = 7, score = 200
            //   0f8497010000         | je                  0x19d
            //   8d9515ebffff         | lea                 edx, [ebp - 0x14eb]
            //   8995b0aeffff         | mov                 dword ptr [ebp - 0x5150], edx
            //   68????????           |                     
            //   8d8515ebffff         | lea                 eax, [ebp - 0x14eb]
            //   50                   | push                eax
            //   ff15????????         |                     

        $sequence_4 = { 52 68???????? 8d85fcf6ffff 50 ff15???????? 83c40c }
            // n = 6, score = 200
            //   52                   | push                edx
            //   68????????           |                     
            //   8d85fcf6ffff         | lea                 eax, [ebp - 0x904]
            //   50                   | push                eax
            //   ff15????????         |                     
            //   83c40c               | add                 esp, 0xc

        $sequence_5 = { 8d8c9000050000 51 6aff 8d953cf9ffff 52 6a00 }
            // n = 6, score = 200
            //   8d8c9000050000       | lea                 ecx, [eax + edx*4 + 0x500]
            //   51                   | push                ecx
            //   6aff                 | push                -1
            //   8d953cf9ffff         | lea                 edx, [ebp - 0x6c4]
            //   52                   | push                edx
            //   6a00                 | push                0

        $sequence_6 = { 8b35???????? 8d8c242c020000 6804010000 51 68???????? ffd6 8dbc242c020000 }
            // n = 7, score = 200
            //   8b35????????         |                     
            //   8d8c242c020000       | lea                 ecx, [esp + 0x22c]
            //   6804010000           | push                0x104
            //   51                   | push                ecx
            //   68????????           |                     
            //   ffd6                 | call                esi
            //   8dbc242c020000       | lea                 edi, [esp + 0x22c]

        $sequence_7 = { 8bfe 8b7638 8b07 50 e8???????? 8b4f04 51 }
            // n = 7, score = 200
            //   8bfe                 | mov                 edi, esi
            //   8b7638               | mov                 esi, dword ptr [esi + 0x38]
            //   8b07                 | mov                 eax, dword ptr [edi]
            //   50                   | push                eax
            //   e8????????           |                     
            //   8b4f04               | mov                 ecx, dword ptr [edi + 4]
            //   51                   | push                ecx

        $sequence_8 = { f3ab 8b842434040000 80fc3a 0f8481000000 80fc3f 7517 }
            // n = 6, score = 200
            //   f3ab                 | rep stosd           dword ptr es:[edi], eax
            //   8b842434040000       | mov                 eax, dword ptr [esp + 0x434]
            //   80fc3a               | cmp                 ah, 0x3a
            //   0f8481000000         | je                  0x87
            //   80fc3f               | cmp                 ah, 0x3f
            //   7517                 | jne                 0x19

        $sequence_9 = { 51 52 ffd6 8b83c8020000 83c408 85c0 }
            // n = 6, score = 200
            //   51                   | push                ecx
            //   52                   | push                edx
            //   ffd6                 | call                esi
            //   8b83c8020000         | mov                 eax, dword ptr [ebx + 0x2c8]
            //   83c408               | add                 esp, 8
            //   85c0                 | test                eax, eax

    condition:
        7 of them and filesize < 327680
}

/*
    This Yara ruleset is under the GNU-GPLv2 license (http://www.gnu.org/licenses/gpl-2.0.html) and open to any user or organization, as    long as you use it under this license.

*/

rule win_evilgrab_w0 {
    meta:
        description = "Vidgrab code tricks"
        author = "Seth Hardy"
        last_modified = "2014-06-20"
		source = "https://github.com/mattulm/sfiles_yara/blob/master/malware/Vidgrab.yar"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.evilgrab"
        malpedia_version = "20170517"
        malpedia_license = "CC BY-NC-SA 4.0"
        malpedia_sharing = "TLP:WHITE"
    strings:
        $divbyzero = { B8 02 00 00 00 48 48 BA 02 00 00 00 83 F2 02 F7 F0 }
        // add eax, ecx; xor byte ptr [eax], ??h; inc ecx
        $xorloop = { 03 C1 80 30 (66 | 58) 41 }
        $junk = { 8B 4? ?? 8B 4? ?? 03 45 08 52 5A }
        
    condition:
        all of them
}

/*
    This Yara ruleset is under the GNU-GPLv2 license (http://www.gnu.org/licenses/gpl-2.0.html) and open to any user or organization, as    long as you use it under this license.

*/

rule win_evilgrab_w1 {
    meta:
        description = "Vidgrab Identifying Strings"
        author = "Seth Hardy"
        last_modified = "2014-06-20"
		source = "https://github.com/mattulm/sfiles_yara/blob/master/malware/Vidgrab.yar"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.evilgrab"
        malpedia_version = "20170517"
        malpedia_license = "CC BY-NC-SA 4.0"
        malpedia_sharing = "TLP:WHITE"
    strings:
        $s1 = "IDI_ICON5" wide ascii
        $s2 = "starter.exe"
        $s3 = "wmifw.exe"
        $s4 = "Software\\rar"
        $s5 = "tmp092.tmp"
        $s6 = "temp1.exe"
        
    condition:
       3 of them
}