SYMBOLCOMMON_NAMEaka. SYNONYMS
win.eyservice (Back to overview)

EYService

Actor(s): Nazar


EYService is the main part of the backdoor used by Nazar APT. This a passive backdoor that relies on, now discontinued, Packet Sniffer SDK (PSSDK) from Microolap.

References
2020-05-05CheckpointCheck Point Research
@online{research:20200505:nazar:a4d2c7c, author = {Check Point Research}, title = {{Nazar: Spirits of the Past}}, date = {2020-05-05}, organization = {Checkpoint}, url = {https://research.checkpoint.com/2020/nazar-spirits-of-the-past/}, language = {English}, urldate = {2020-05-05} } Nazar: Spirits of the Past
EYService
2020-04-27MalwareLab.plMaciej Kotowicz
@online{kotowicz:20200427:quick:e6bf310, author = {Maciej Kotowicz}, title = {{Quick look at Nazar's backdoor - Network Communication}}, date = {2020-04-27}, organization = {MalwareLab.pl}, url = {https://blog.malwarelab.pl/posts/nazar_eyservice_comm/}, language = {English}, urldate = {2020-05-05} } Quick look at Nazar's backdoor - Network Communication
EYService
2020-04-23MalwareLab.plMaciej Kotowicz
@online{kotowicz:20200423:quick:ce2218e, author = {Maciej Kotowicz}, title = {{Quick look at Nazar backdoor - Capabilities}}, date = {2020-04-23}, organization = {MalwareLab.pl}, url = {https://blog.malwarelab.pl/posts/nazar_eyservice/}, language = {English}, urldate = {2020-05-05} } Quick look at Nazar backdoor - Capabilities
EYService
2020-04-22EpicTurlaJuan Andrés Guerrero-Saade
@online{guerrerosaade:20200422:nazar:0c5eef8, author = {Juan Andrés Guerrero-Saade}, title = {{Nazar: A Lost Amulet}}, date = {2020-04-22}, organization = {EpicTurla}, url = {https://www.epicturla.com/blog/the-lost-nazar}, language = {English}, urldate = {2020-05-05} } Nazar: A Lost Amulet
EYService Nazar
2018-03CrySyS LabBoldizsar Bencsath
@techreport{bencsath:201803:territorial:04343bb, author = {Boldizsar Bencsath}, title = {{Territorial Dispute – NSA’s perspective on APT landscape}}, date = {2018-03}, institution = {CrySyS Lab}, url = {https://www.crysys.hu/publications/files/tedi/ukatemicrysys_territorialdispute.pdf}, language = {English}, urldate = {2020-05-07} } Territorial Dispute – NSA’s perspective on APT landscape
9002 RAT Agent.BTZ DuQu EYService Flame FlowerShop Stuxnet Uroburos
Yara Rules
[TLP:WHITE] win_eyservice_auto (20201014 | autogenerated rule brought to you by yara-signator)
rule win_eyservice_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2020-10-14"
        version = "1"
        description = "autogenerated rule brought to you by yara-signator"
        tool = "yara-signator v0.5.0"
        tool_config = "callsandjumps;datarefs;binvalue"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.eyservice"
        malpedia_rule_date = "20201014"
        malpedia_hash = "a7e3bd57eaf12bf3ea29a863c041091ba3af9ac9"
        malpedia_version = "20201014"
        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 = { 896c2414 3bdd 0f86df000000 8bce e8???????? }
            // n = 5, score = 100
            //   896c2414             | mov                 dword ptr [esp + 0x14], ebp
            //   3bdd                 | cmp                 ebx, ebp
            //   0f86df000000         | jbe                 0xe5
            //   8bce                 | mov                 ecx, esi
            //   e8????????           |                     

        $sequence_1 = { 7404 3bf8 7406 ff15???????? 3bf3 735b 8b1d???????? }
            // n = 7, score = 100
            //   7404                 | je                  6
            //   3bf8                 | cmp                 edi, eax
            //   7406                 | je                  8
            //   ff15????????         |                     
            //   3bf3                 | cmp                 esi, ebx
            //   735b                 | jae                 0x5d
            //   8b1d????????         |                     

        $sequence_2 = { 750d ffd3 3b7710 7202 ffd3 8b36 eb08 }
            // n = 7, score = 100
            //   750d                 | jne                 0xf
            //   ffd3                 | call                ebx
            //   3b7710               | cmp                 esi, dword ptr [edi + 0x10]
            //   7202                 | jb                  4
            //   ffd3                 | call                ebx
            //   8b36                 | mov                 esi, dword ptr [esi]
            //   eb08                 | jmp                 0xa

        $sequence_3 = { 56 8bf1 85db 7426 8b4e28 8b06 }
            // n = 6, score = 100
            //   56                   | push                esi
            //   8bf1                 | mov                 esi, ecx
            //   85db                 | test                ebx, ebx
            //   7426                 | je                  0x28
            //   8b4e28               | mov                 ecx, dword ptr [esi + 0x28]
            //   8b06                 | mov                 eax, dword ptr [esi]

        $sequence_4 = { 6a06 8d4c2462 03d0 68???????? }
            // n = 4, score = 100
            //   6a06                 | push                6
            //   8d4c2462             | lea                 ecx, [esp + 0x62]
            //   03d0                 | add                 edx, eax
            //   68????????           |                     

        $sequence_5 = { 50 ffd5 8d4c2414 51 6819000200 6a00 68???????? }
            // n = 7, score = 100
            //   50                   | push                eax
            //   ffd5                 | call                ebp
            //   8d4c2414             | lea                 ecx, [esp + 0x14]
            //   51                   | push                ecx
            //   6819000200           | push                0x20019
            //   6a00                 | push                0
            //   68????????           |                     

        $sequence_6 = { 8b5c2434 55 8b6c2444 56 }
            // n = 4, score = 100
            //   8b5c2434             | mov                 ebx, dword ptr [esp + 0x34]
            //   55                   | push                ebp
            //   8b6c2444             | mov                 ebp, dword ptr [esp + 0x44]
            //   56                   | push                esi

        $sequence_7 = { 6808020000 83c608 56 e8???????? eb42 8b533c 8d4608 }
            // n = 7, score = 100
            //   6808020000           | push                0x208
            //   83c608               | add                 esi, 8
            //   56                   | push                esi
            //   e8????????           |                     
            //   eb42                 | jmp                 0x44
            //   8b533c               | mov                 edx, dword ptr [ebx + 0x3c]
            //   8d4608               | lea                 eax, [esi + 8]

        $sequence_8 = { 89842410030000 833d????????00 56 743b 6804010000 8d44240c 50 }
            // n = 7, score = 100
            //   89842410030000       | mov                 dword ptr [esp + 0x310], eax
            //   833d????????00       |                     
            //   56                   | push                esi
            //   743b                 | je                  0x3d
            //   6804010000           | push                0x104
            //   8d44240c             | lea                 eax, [esp + 0xc]
            //   50                   | push                eax

        $sequence_9 = { e8???????? 33db 8d4c2414 899c24c8830000 e8???????? c68424c883000001 391d???????? }
            // n = 7, score = 100
            //   e8????????           |                     
            //   33db                 | xor                 ebx, ebx
            //   8d4c2414             | lea                 ecx, [esp + 0x14]
            //   899c24c8830000       | mov                 dword ptr [esp + 0x83c8], ebx
            //   e8????????           |                     
            //   c68424c883000001     | mov                 byte ptr [esp + 0x83c8], 1
            //   391d????????         |                     

    condition:
        7 of them and filesize < 452608
}
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