rule win_cosmicduke_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2024-10-31"
        version = "1"
        description = "Detects win.cosmicduke."
        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.cosmicduke"
        malpedia_rule_date = "20241030"
        malpedia_hash = "26e26953c49c8efafbf72a38076855d578e0a2e4"
        malpedia_version = "20241030"
        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???????? 8db514ffffff e9???????? 8db504ffffff e9???????? b8???????? e9???????? }
            // n = 7, score = 100
            //   e9????????           |                     
            //   8db514ffffff         | lea                 esi, [ebp - 0xec]
            //   e9????????           |                     
            //   8db504ffffff         | lea                 esi, [ebp - 0xfc]
            //   e9????????           |                     
            //   b8????????           |                     
            //   e9????????           |                     

        $sequence_1 = { ff15???????? 6a02 6a02 6800000040 ff7510 53 ff15???????? }
            // n = 7, score = 100
            //   ff15????????         |                     
            //   6a02                 | push                2
            //   6a02                 | push                2
            //   6800000040           | push                0x40000000
            //   ff7510               | push                dword ptr [ebp + 0x10]
            //   53                   | push                ebx
            //   ff15????????         |                     

        $sequence_2 = { c644240f01 85f6 0f8594000000 ff742418 8d842414010000 ff742428 }
            // n = 6, score = 100
            //   c644240f01           | mov                 byte ptr [esp + 0xf], 1
            //   85f6                 | test                esi, esi
            //   0f8594000000         | jne                 0x9a
            //   ff742418             | push                dword ptr [esp + 0x18]
            //   8d842414010000       | lea                 eax, [esp + 0x114]
            //   ff742428             | push                dword ptr [esp + 0x28]

        $sequence_3 = { 668985ecfeffff 0fb645fb 50 0fb645fa 50 0fb645f9 }
            // n = 6, score = 100
            //   668985ecfeffff       | mov                 word ptr [ebp - 0x114], ax
            //   0fb645fb             | movzx               eax, byte ptr [ebp - 5]
            //   50                   | push                eax
            //   0fb645fa             | movzx               eax, byte ptr [ebp - 6]
            //   50                   | push                eax
            //   0fb645f9             | movzx               eax, byte ptr [ebp - 7]

        $sequence_4 = { 56 ff15???????? 885c2417 ebdd 33c9 394c2408 7e0f }
            // n = 7, score = 100
            //   56                   | push                esi
            //   ff15????????         |                     
            //   885c2417             | mov                 byte ptr [esp + 0x17], bl
            //   ebdd                 | jmp                 0xffffffdf
            //   33c9                 | xor                 ecx, ecx
            //   394c2408             | cmp                 dword ptr [esp + 8], ecx
            //   7e0f                 | jle                 0x11

        $sequence_5 = { 5f 85c0 7444 8b442454 8944240c 53 8d442414 }
            // n = 7, score = 100
            //   5f                   | pop                 edi
            //   85c0                 | test                eax, eax
            //   7444                 | je                  0x46
            //   8b442454             | mov                 eax, dword ptr [esp + 0x54]
            //   8944240c             | mov                 dword ptr [esp + 0xc], eax
            //   53                   | push                ebx
            //   8d442414             | lea                 eax, [esp + 0x14]

        $sequence_6 = { 83ffff 7416 8d45e4 50 57 ff15???????? 85c0 }
            // n = 7, score = 100
            //   83ffff               | cmp                 edi, -1
            //   7416                 | je                  0x18
            //   8d45e4               | lea                 eax, [ebp - 0x1c]
            //   50                   | push                eax
            //   57                   | push                edi
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax

        $sequence_7 = { 8bf8 8a8358020000 8bf3 8845ff e8???????? 84c0 0f84ae000000 }
            // n = 7, score = 100
            //   8bf8                 | mov                 edi, eax
            //   8a8358020000         | mov                 al, byte ptr [ebx + 0x258]
            //   8bf3                 | mov                 esi, ebx
            //   8845ff               | mov                 byte ptr [ebp - 1], al
            //   e8????????           |                     
            //   84c0                 | test                al, al
            //   0f84ae000000         | je                  0xb4

        $sequence_8 = { 53 53 8d44242c 50 ff15???????? 85c0 740d }
            // n = 7, score = 100
            //   53                   | push                ebx
            //   53                   | push                ebx
            //   8d44242c             | lea                 eax, [esp + 0x2c]
            //   50                   | push                eax
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax
            //   740d                 | je                  0xf

        $sequence_9 = { 8b1d???????? 83c40c 8d842490000000 50 8d842414010000 50 ffd3 }
            // n = 7, score = 100
            //   8b1d????????         |                     
            //   83c40c               | add                 esp, 0xc
            //   8d842490000000       | lea                 eax, [esp + 0x90]
            //   50                   | push                eax
            //   8d842414010000       | lea                 eax, [esp + 0x114]
            //   50                   | push                eax
            //   ffd3                 | call                ebx

    condition:
        7 of them and filesize < 456704
}

rule win_cosmicduke_w0 {
	meta:
	    description = "detect cosmicduke"
	    author = "@malgamy12"
        date = "2022-11-6"
	    license = "DRL 1.1"
	    hash_sample1 = "93054d3abc36019ccfe88f87363363e6ca9b77f4"
        hash_sample2 = "0eadbd6ef9f5930257530ac5a3b8abb49c9755d1"
        hash_sample3 = "69c2d292179dc615bfe4d7f880b5f9928604558e"
        hash_sample4 = "616306489de4029da7271eadbdf090cee22ae1af"
        hash_sample5 = "ecb8edfddd812a125b515dc42a2e93569c1caed9"
        hash_sample6 = "a86f3faf1eedb7325023616adf37a62c9129c24e"
        hash_sample7 = "4d22b2d85b75ccf651f0ba85808482660a440bff"
        hash_sample8 = "3463df6b33b26c1249207f6e004c0bbc31b31152"
        hash_sample9 = "ca4c53eb86d5b920b321de573e212e31405707d5"
        hash_sample10 = "a48e4dd017618ae2d46a753345594a5f57fbe869"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.cosmicduke"
        malpedia_rule_date = "20230118"
        malpedia_hash = ""
        malpedia_version = "20230118"
        malpedia_license = "DRL 1.1"
        malpedia_sharing = "TLP:WHITE"
    strings:
        $pdb = "5\\bin\\bot.pdb" ascii

        $s1 = "pipe\\40DC244D-F62E-093E-8A91-736FF2FA2AA2" wide
        $s2 = "LoginName" ascii	
        $s3 = "select id, hostname, usernamefield, passwordfield, encryptedusern" wide
        $s4 = "*temporary;*Cookies;*games;*system32;*program files;*\\windows\\;*\\System Volume Information" wide
        $s5 = "msicheck.cmd" ascii
        $s6 = "AppData\\Roaming\\Miranda"  wide 
        $s7 = "Local Settings\\Application Data" wide
	
	/*
	imul    ebx, esi
        imul    esi, 0BC8Fh
        mov     eax, edx
        and     eax, 3
        lea     eax, [ebp+eax*4+var_3C]
        xor     [eax], ebx
        inc     edx
        dec     [ebp+var_8]
	*/

        $chunk_1 = {0F AF DE 69 F6 ?? ?? ?? ?? 8B C2 83 E0 ?? 8D 44 85 ?? 31 18 42 FF 4D ??}   

    condition:
        uint16(0) == 0x5A4D and filesize > 70KB and ($pdb  or  (4 of ($s*) and $chunk_1 ))
}