rule win_naikon_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.naikon."
        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.naikon"
        malpedia_rule_date = "20260422"
        malpedia_hash = "a182e35da64e6d71cb55f125c4d4225196523f14"
        malpedia_version = "20260504"
        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 = { ff75e8 ff5040 8b436c ff750c ff5024 }
            // n = 5, score = 200
            //   ff75e8               | push                dword ptr [ebp - 0x18]
            //   ff5040               | call                dword ptr [eax + 0x40]
            //   8b436c               | mov                 eax, dword ptr [ebx + 0x6c]
            //   ff750c               | push                dword ptr [ebp + 0xc]
            //   ff5024               | call                dword ptr [eax + 0x24]

        $sequence_1 = { 8d459c 8945e8 53 8d45e0 53 50 }
            // n = 6, score = 200
            //   8d459c               | lea                 eax, [ebp - 0x64]
            //   8945e8               | mov                 dword ptr [ebp - 0x18], eax
            //   53                   | push                ebx
            //   8d45e0               | lea                 eax, [ebp - 0x20]
            //   53                   | push                ebx
            //   50                   | push                eax

        $sequence_2 = { 59 74bd 68???????? e8???????? 03d8 }
            // n = 5, score = 200
            //   59                   | pop                 ecx
            //   74bd                 | je                  0xffffffbf
            //   68????????           |                     
            //   e8????????           |                     
            //   03d8                 | add                 ebx, eax

        $sequence_3 = { e8???????? 83c424 8d45ac 897dac 50 8d45e0 }
            // n = 6, score = 200
            //   e8????????           |                     
            //   83c424               | add                 esp, 0x24
            //   8d45ac               | lea                 eax, [ebp - 0x54]
            //   897dac               | mov                 dword ptr [ebp - 0x54], edi
            //   50                   | push                eax
            //   8d45e0               | lea                 eax, [ebp - 0x20]

        $sequence_4 = { 5f 5e c3 55 8bec 81ec340a0000 }
            // n = 6, score = 200
            //   5f                   | pop                 edi
            //   5e                   | pop                 esi
            //   c3                   | ret                 
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp
            //   81ec340a0000         | sub                 esp, 0xa34

        $sequence_5 = { 8bf8 83ffff 0f84bf000000 85ff 0f84b7000000 8d85d4efffff }
            // n = 6, score = 200
            //   8bf8                 | mov                 edi, eax
            //   83ffff               | cmp                 edi, -1
            //   0f84bf000000         | je                  0xc5
            //   85ff                 | test                edi, edi
            //   0f84b7000000         | je                  0xbd
            //   8d85d4efffff         | lea                 eax, [ebp - 0x102c]

        $sequence_6 = { 50 68???????? 53 e8???????? 8d8570fdffff 6a3e }
            // n = 6, score = 200
            //   50                   | push                eax
            //   68????????           |                     
            //   53                   | push                ebx
            //   e8????????           |                     
            //   8d8570fdffff         | lea                 eax, [ebp - 0x290]
            //   6a3e                 | push                0x3e

        $sequence_7 = { 50 ff75fc e8???????? 53 8945f4 ffd7 837df400 }
            // n = 7, score = 200
            //   50                   | push                eax
            //   ff75fc               | push                dword ptr [ebp - 4]
            //   e8????????           |                     
            //   53                   | push                ebx
            //   8945f4               | mov                 dword ptr [ebp - 0xc], eax
            //   ffd7                 | call                edi
            //   837df400             | cmp                 dword ptr [ebp - 0xc], 0

        $sequence_8 = { 55 8bec 81ec90010000 8d8570feffff 50 6a02 e8???????? }
            // n = 7, score = 200
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp
            //   81ec90010000         | sub                 esp, 0x190
            //   8d8570feffff         | lea                 eax, [ebp - 0x190]
            //   50                   | push                eax
            //   6a02                 | push                2
            //   e8????????           |                     

        $sequence_9 = { ff7508 eb17 6a00 8bce e8???????? 8b06 8b4e08 }
            // n = 7, score = 200
            //   ff7508               | push                dword ptr [ebp + 8]
            //   eb17                 | jmp                 0x19
            //   6a00                 | push                0
            //   8bce                 | mov                 ecx, esi
            //   e8????????           |                     
            //   8b06                 | mov                 eax, dword ptr [esi]
            //   8b4e08               | mov                 ecx, dword ptr [esi + 8]

    condition:
        7 of them and filesize < 188416
}

/*
    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_naikon_w0 {
    meta:
        description = "Naikon code features"
        author = "Seth Hardy"
        last_modified = "2014-06-25"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.naikon"
        malpedia_version = "20170618"
        malpedia_license = "CC BY-NC-SA 4.0"
        malpedia_sharing = "TLP:WHITE"
    
    strings:
        // decryption
        $ = { 0F AF C1 C1 E0 1F } // imul eax, ecx; shl eah, 1fh
        $ = { 35 5A 01 00 00} // xor eax, 15ah
        $ = { 81 C2 7F 14 06 00 } // add edx, 6147fh
    
    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_naikon_w1 {
    meta:
        description = "Naikon Identifying Strings"
        author = "Seth Hardy"
        last_modified = "2014-06-25"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.naikon"
        malpedia_version = "20170618"
        malpedia_license = "CC BY-NC-SA 4.0"
        malpedia_sharing = "TLP:WHITE"
        
    strings:
        $ = "NOKIAN95/WEB"
        $ = "/tag=info&id=15"
        $ = "skg(3)=&3.2d_u1"
        $ = "\\Temp\\iExplorer.exe"
        $ = "\\Temp\\\"TSG\""
        
    condition:
       any of them
}

rule win_naikon_w2 {
    meta:
        description = "Detects backdoors related to the Naikon APT"
        author = "Florian Roth"
        reference = "https://goo.gl/7vHyvh"
        date = "2015-05-14"
        hash = "d5716c80cba8554eb79eecfb4aa3d99faf0435a1833ec5ef51f528146c758eba"
        hash = "f5ab8e49c0778fa208baad660fe4fa40fc8a114f5f71614afbd6dcc09625cb96"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.naikon"
        malpedia_version = "20170618"
        malpedia_license = "CC BY-NC-SA 4.0"
        malpedia_sharing = "TLP:WHITE"

    strings:
        $x0 = "GET http://%s:%d/aspxabcdef.asp?%s HTTP/1.1" fullword ascii
        $x1 = "POST http://%s:%d/aspxabcdefg.asp?%s HTTP/1.1" fullword ascii
        $x2 = "greensky27.vicp.net" fullword ascii
        $x3 = "\\tempvxd.vxd.dll" fullword wide
        $x4 = "otna.vicp.net" fullword ascii
        $x5 = "smithking19.gicp.net" fullword ascii

        $s1 = "User-Agent: webclient" fullword ascii
        $s2 = "\\User.ini" fullword ascii
        $s3 = "User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-EN; rv:1.7.12) Gecko/200" ascii
        $s4 = "\\UserProfile.dll" fullword wide
        $s5 = "Connection:Keep-Alive: %d" fullword ascii
        $s6 = "Referer: http://%s:%d/" fullword ascii
        $s7 = "%s %s %s %d %d %d " fullword ascii
        $s8 = "%s--%s" fullword wide
        $s9 = "Run File Success!" fullword wide
        $s10 = "DRIVE_REMOTE" fullword wide
        $s11 = "ProxyEnable" fullword wide
        $s12 = "\\cmd.exe" fullword wide

    condition:
        uint16(0) == 0x5a4d and filesize < 1000KB and (1 of ($x*) or 7 of ($s*))
}