rule win_zerot_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2023-01-25"
        version = "1"
        description = "Detects win.zerot."
        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.zerot"
        malpedia_rule_date = "20230124"
        malpedia_hash = "2ee0eebba83dce3d019a90519f2f972c0fcf9686"
        malpedia_version = "20230125"
        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 = { b8cc320000 e8???????? a1???????? 33c5 }
            // n = 4, score = 200
            //   b8cc320000           | mov                 eax, 0x32cc
            //   e8????????           |                     
            //   a1????????           |                     
            //   33c5                 | xor                 eax, ebp

        $sequence_1 = { 8b45e8 881430 8a4ffc 02c9 02ca 8bd0 880c32 }
            // n = 7, score = 200
            //   8b45e8               | mov                 eax, dword ptr [ebp - 0x18]
            //   881430               | mov                 byte ptr [eax + esi], dl
            //   8a4ffc               | mov                 cl, byte ptr [edi - 4]
            //   02c9                 | add                 cl, cl
            //   02ca                 | add                 cl, dl
            //   8bd0                 | mov                 edx, eax
            //   880c32               | mov                 byte ptr [edx + esi], cl

        $sequence_2 = { 68ff010f00 50 50 ffb52cf6ffff ff15???????? 8bf0 }
            // n = 6, score = 200
            //   68ff010f00           | push                0xf01ff
            //   50                   | push                eax
            //   50                   | push                eax
            //   ffb52cf6ffff         | push                dword ptr [ebp - 0x9d4]
            //   ff15????????         |                     
            //   8bf0                 | mov                 esi, eax

        $sequence_3 = { 0f847a030000 57 8d8528fdffff 50 68???????? }
            // n = 5, score = 200
            //   0f847a030000         | je                  0x380
            //   57                   | push                edi
            //   8d8528fdffff         | lea                 eax, [ebp - 0x2d8]
            //   50                   | push                eax
            //   68????????           |                     

        $sequence_4 = { ff760c e8???????? ff35???????? e8???????? 8b45ec 50 }
            // n = 6, score = 200
            //   ff760c               | push                dword ptr [esi + 0xc]
            //   e8????????           |                     
            //   ff35????????         |                     
            //   e8????????           |                     
            //   8b45ec               | mov                 eax, dword ptr [ebp - 0x14]
            //   50                   | push                eax

        $sequence_5 = { 8d4590 50 0f1145d1 660fd645e1 e8???????? }
            // n = 5, score = 200
            //   8d4590               | lea                 eax, [ebp - 0x70]
            //   50                   | push                eax
            //   0f1145d1             | movups              xmmword ptr [ebp - 0x2f], xmm0
            //   660fd645e1           | movq                qword ptr [ebp - 0x1f], xmm0
            //   e8????????           |                     

        $sequence_6 = { 6880000000 8d853cfeffff 6a00 50 e8???????? ffb534f6ffff }
            // n = 6, score = 200
            //   6880000000           | push                0x80
            //   8d853cfeffff         | lea                 eax, [ebp - 0x1c4]
            //   6a00                 | push                0
            //   50                   | push                eax
            //   e8????????           |                     
            //   ffb534f6ffff         | push                dword ptr [ebp - 0x9cc]

        $sequence_7 = { 8d8fff010000 898530cdffff 51 6a00 }
            // n = 4, score = 200
            //   8d8fff010000         | lea                 ecx, [edi + 0x1ff]
            //   898530cdffff         | mov                 dword ptr [ebp - 0x32d0], eax
            //   51                   | push                ecx
            //   6a00                 | push                0

        $sequence_8 = { 84c0 75f9 2bca 51 53 6a07 }
            // n = 6, score = 200
            //   84c0                 | test                al, al
            //   75f9                 | jne                 0xfffffffb
            //   2bca                 | sub                 ecx, edx
            //   51                   | push                ecx
            //   53                   | push                ebx
            //   6a07                 | push                7

        $sequence_9 = { 898530fcffff 90 33db bf01000000 }
            // n = 4, score = 200
            //   898530fcffff         | mov                 dword ptr [ebp - 0x3d0], eax
            //   90                   | nop                 
            //   33db                 | xor                 ebx, ebx
            //   bf01000000           | mov                 edi, 1

    condition:
        7 of them and filesize < 303104
}

rule win_zerot_w0 {
    meta:
        description = "Detects malware from the Proofpoint CN APT ZeroT incident"
        author = "Florian Roth"
        reference = "https://www.proofpoint.com/us/threat-insight/post/APT-targets-russia-belarus-zerot-plugx"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.zerot"
        malpedia_version = "20180301"
        malpedia_license = "CC BY-NC-SA 4.0"
        malpedia_sharing = "TLP:WHITE"
    strings:
        $s6 = "jGetgQ|0h9=" fullword ascii
    condition:
        ( 10 of ($s*) ) or ( all of them )
}