rule win_koobface_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2022-08-05"
        version = "1"
        description = "Detects win.koobface."
        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.koobface"
        malpedia_rule_date = "20220805"
        malpedia_hash = "6ec06c64bcfdbeda64eff021c766b4ce34542b71"
        malpedia_version = "20220808"
        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 = { 8bcf 83e11f c1e106 8b0485a0534200 c644080401 57 e8???????? }
            // n = 7, score = 100
            //   8bcf                 | mov                 ecx, edi
            //   83e11f               | and                 ecx, 0x1f
            //   c1e106               | shl                 ecx, 6
            //   8b0485a0534200       | mov                 eax, dword ptr [eax*4 + 0x4253a0]
            //   c644080401           | mov                 byte ptr [eax + ecx + 4], 1
            //   57                   | push                edi
            //   e8????????           |                     

        $sequence_1 = { 50 57 c645fc07 ff5124 ff75d0 ff15???????? 895d08 }
            // n = 7, score = 100
            //   50                   | push                eax
            //   57                   | push                edi
            //   c645fc07             | mov                 byte ptr [ebp - 4], 7
            //   ff5124               | call                dword ptr [ecx + 0x24]
            //   ff75d0               | push                dword ptr [ebp - 0x30]
            //   ff15????????         |                     
            //   895d08               | mov                 dword ptr [ebp + 8], ebx

        $sequence_2 = { 85c0 7406 8b08 50 ff5108 8b8528f4ffff c645fc04 }
            // n = 7, score = 100
            //   85c0                 | test                eax, eax
            //   7406                 | je                  8
            //   8b08                 | mov                 ecx, dword ptr [eax]
            //   50                   | push                eax
            //   ff5108               | call                dword ptr [ecx + 8]
            //   8b8528f4ffff         | mov                 eax, dword ptr [ebp - 0xbd8]
            //   c645fc04             | mov                 byte ptr [ebp - 4], 4

        $sequence_3 = { ff750c e8???????? 83ee80 56 e8???????? 83c418 }
            // n = 6, score = 100
            //   ff750c               | push                dword ptr [ebp + 0xc]
            //   e8????????           |                     
            //   83ee80               | sub                 esi, -0x80
            //   56                   | push                esi
            //   e8????????           |                     
            //   83c418               | add                 esp, 0x18

        $sequence_4 = { ff513c 8b45dc 3bc3 0f84ee010000 8b08 8d55e0 52 }
            // n = 7, score = 100
            //   ff513c               | call                dword ptr [ecx + 0x3c]
            //   8b45dc               | mov                 eax, dword ptr [ebp - 0x24]
            //   3bc3                 | cmp                 eax, ebx
            //   0f84ee010000         | je                  0x1f4
            //   8b08                 | mov                 ecx, dword ptr [eax]
            //   8d55e0               | lea                 edx, [ebp - 0x20]
            //   52                   | push                edx

        $sequence_5 = { 8b4dfc 33cd 33c0 e8???????? c9 c20400 e9???????? }
            // n = 7, score = 100
            //   8b4dfc               | mov                 ecx, dword ptr [ebp - 4]
            //   33cd                 | xor                 ecx, ebp
            //   33c0                 | xor                 eax, eax
            //   e8????????           |                     
            //   c9                   | leave               
            //   c20400               | ret                 4
            //   e9????????           |                     

        $sequence_6 = { 8b8528f4ffff 85c0 0f84c3000000 83a52cf4ffff00 8b08 8d952cf4ffff 52 }
            // n = 7, score = 100
            //   8b8528f4ffff         | mov                 eax, dword ptr [ebp - 0xbd8]
            //   85c0                 | test                eax, eax
            //   0f84c3000000         | je                  0xc9
            //   83a52cf4ffff00       | and                 dword ptr [ebp - 0xbd4], 0
            //   8b08                 | mov                 ecx, dword ptr [eax]
            //   8d952cf4ffff         | lea                 edx, [ebp - 0xbd4]
            //   52                   | push                edx

        $sequence_7 = { 0f843b020000 895ddc 895de0 8b08 }
            // n = 4, score = 100
            //   0f843b020000         | je                  0x241
            //   895ddc               | mov                 dword ptr [ebp - 0x24], ebx
            //   895de0               | mov                 dword ptr [ebp - 0x20], ebx
            //   8b08                 | mov                 ecx, dword ptr [eax]

        $sequence_8 = { 8d850cffffff c745fc06000000 50 8b8dccfdffff e8???????? 834dfcff 53 }
            // n = 7, score = 100
            //   8d850cffffff         | lea                 eax, [ebp - 0xf4]
            //   c745fc06000000       | mov                 dword ptr [ebp - 4], 6
            //   50                   | push                eax
            //   8b8dccfdffff         | mov                 ecx, dword ptr [ebp - 0x234]
            //   e8????????           |                     
            //   834dfcff             | or                  dword ptr [ebp - 4], 0xffffffff
            //   53                   | push                ebx

        $sequence_9 = { ff5108 8b45ec c645fc03 3bc3 7406 8b08 50 }
            // n = 7, score = 100
            //   ff5108               | call                dword ptr [ecx + 8]
            //   8b45ec               | mov                 eax, dword ptr [ebp - 0x14]
            //   c645fc03             | mov                 byte ptr [ebp - 4], 3
            //   3bc3                 | cmp                 eax, ebx
            //   7406                 | je                  8
            //   8b08                 | mov                 ecx, dword ptr [eax]
            //   50                   | push                eax

    condition:
        7 of them and filesize < 368640
}