SYMBOLCOMMON_NAMEaka. SYNONYMS
win.polyglot_ransom (Back to overview)

Polyglot


There is no description at this point.

References
2016-10-03Kaspersky LabsAnton Ivanov, Orkhan Mamedov, Fedor Sinitsyn
@online{ivanov:20161003:polyglot:6fe8657, author = {Anton Ivanov and Orkhan Mamedov and Fedor Sinitsyn}, title = {{Polyglot – the fake CTB-locker}}, date = {2016-10-03}, organization = {Kaspersky Labs}, url = {https://securelist.com/blog/research/76182/polyglot-the-fake-ctb-locker/}, language = {English}, urldate = {2019-12-20} } Polyglot – the fake CTB-locker
Polyglot
Yara Rules
[TLP:WHITE] win_polyglot_ransom_auto (20230125 | Detects win.polyglot_ransom.)
rule win_polyglot_ransom_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2023-01-25"
        version = "1"
        description = "Detects win.polyglot_ransom."
        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.polyglot_ransom"
        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 = { 8bf0 83e61f 8d3c8d809b4800 8b0f c1e606 833c0eff 7536 }
            // n = 7, score = 100
            //   8bf0                 | mov                 esi, eax
            //   83e61f               | and                 esi, 0x1f
            //   8d3c8d809b4800       | lea                 edi, [ecx*4 + 0x489b80]
            //   8b0f                 | mov                 ecx, dword ptr [edi]
            //   c1e606               | shl                 esi, 6
            //   833c0eff             | cmp                 dword ptr [esi + ecx], -1
            //   7536                 | jne                 0x38

        $sequence_1 = { 80d0b5 d182d0bdd0be d0b3d0be20d0 bad0bbd18e d187d0b020d0 bdd0b520d0 b2d0 }
            // n = 7, score = 100
            //   80d0b5               | adc                 al, 0xb5
            //   d182d0bdd0be         | rol                 dword ptr [edx - 0x412f4230], 1
            //   d0b3d0be20d0         | sal                 byte ptr [ebx - 0x2fdf4130], 1
            //   bad0bbd18e           | mov                 edx, 0x8ed1bbd0
            //   d187d0b020d0         | rol                 dword ptr [edi - 0x2fdf4f30], 1
            //   bdd0b520d0           | mov                 ebp, 0xd020b5d0
            //   b2d0                 | mov                 dl, 0xd0

        $sequence_2 = { 8b7e04 85ff 741e 8b4e08 8b4108 53 8b1f }
            // n = 7, score = 100
            //   8b7e04               | mov                 edi, dword ptr [esi + 4]
            //   85ff                 | test                edi, edi
            //   741e                 | je                  0x20
            //   8b4e08               | mov                 ecx, dword ptr [esi + 8]
            //   8b4108               | mov                 eax, dword ptr [ecx + 8]
            //   53                   | push                ebx
            //   8b1f                 | mov                 ebx, dword ptr [edi]

        $sequence_3 = { a900000100 74c6 5f 5e 8bc3 5b c20800 }
            // n = 7, score = 100
            //   a900000100           | test                eax, 0x10000
            //   74c6                 | je                  0xffffffc8
            //   5f                   | pop                 edi
            //   5e                   | pop                 esi
            //   8bc3                 | mov                 eax, ebx
            //   5b                   | pop                 ebx
            //   c20800               | ret                 8

        $sequence_4 = { c9 c3 53 56 57 68???????? ff742414 }
            // n = 7, score = 100
            //   c9                   | leave               
            //   c3                   | ret                 
            //   53                   | push                ebx
            //   56                   | push                esi
            //   57                   | push                edi
            //   68????????           |                     
            //   ff742414             | push                dword ptr [esp + 0x14]

        $sequence_5 = { 57 8d458c 50 6a25 e8???????? 8d4510 50 }
            // n = 7, score = 100
            //   57                   | push                edi
            //   8d458c               | lea                 eax, [ebp - 0x74]
            //   50                   | push                eax
            //   6a25                 | push                0x25
            //   e8????????           |                     
            //   8d4510               | lea                 eax, [ebp + 0x10]
            //   50                   | push                eax

        $sequence_6 = { e8???????? c20800 6a2c b8???????? e8???????? 8b7508 ffb644ffffff }
            // n = 7, score = 100
            //   e8????????           |                     
            //   c20800               | ret                 8
            //   6a2c                 | push                0x2c
            //   b8????????           |                     
            //   e8????????           |                     
            //   8b7508               | mov                 esi, dword ptr [ebp + 8]
            //   ffb644ffffff         | push                dword ptr [esi - 0xbc]

        $sequence_7 = { c1e004 8b0430 83f802 0f8455010000 83f801 0f844c010000 8b4a04 }
            // n = 7, score = 100
            //   c1e004               | shl                 eax, 4
            //   8b0430               | mov                 eax, dword ptr [eax + esi]
            //   83f802               | cmp                 eax, 2
            //   0f8455010000         | je                  0x15b
            //   83f801               | cmp                 eax, 1
            //   0f844c010000         | je                  0x152
            //   8b4a04               | mov                 ecx, dword ptr [edx + 4]

        $sequence_8 = { 636966 7261 646f 206175 746f 6d 61 }
            // n = 7, score = 100
            //   636966               | arpl                word ptr [ecx + 0x66], bp
            //   7261                 | jb                  0x63
            //   646f                 | outsd               dx, dword ptr fs:[esi]
            //   206175               | and                 byte ptr [ecx + 0x75], ah
            //   746f                 | je                  0x71
            //   6d                   | insd                dword ptr es:[edi], dx
            //   61                   | popal               

        $sequence_9 = { 8365d800 8b07 8d4dd8 51 68???????? 57 c645fc01 }
            // n = 7, score = 100
            //   8365d800             | and                 dword ptr [ebp - 0x28], 0
            //   8b07                 | mov                 eax, dword ptr [edi]
            //   8d4dd8               | lea                 ecx, [ebp - 0x28]
            //   51                   | push                ecx
            //   68????????           |                     
            //   57                   | push                edi
            //   c645fc01             | mov                 byte ptr [ebp - 4], 1

    condition:
        7 of them and filesize < 1392640
}
Download all Yara Rules