SYMBOLCOMMON_NAMEaka. SYNONYMS
win.neshta (Back to overview)

neshta


Neshta is a 2005 Belarusian file infector virus written in Delphi. The name of the virus comes from the Belarusian word "nesta" meaning "something."

References
2021-10-27MandiantKen Proska, Corey Hildebrandt, Daniel Kapellmann Zafra, Nathan Brubaker
@online{proska:20211027:portable:437b9c1, author = {Ken Proska and Corey Hildebrandt and Daniel Kapellmann Zafra and Nathan Brubaker}, title = {{Portable Executable File Infecting Malware Is Increasingly Found in OT Networks}}, date = {2021-10-27}, organization = {Mandiant}, url = {https://www.mandiant.com/resources/pe-file-infecting-malware-ot}, language = {English}, urldate = {2021-11-08} } Portable Executable File Infecting Malware Is Increasingly Found in OT Networks
CCleaner Backdoor Floxif neshta Ramnit Sality Virut
2019-10-29BlackberryTatsuya Hasegawa
@online{hasegawa:20191029:threat:180cf21, author = {Tatsuya Hasegawa}, title = {{Threat Spotlight: Neshta File Infector Endures}}, date = {2019-10-29}, organization = {Blackberry}, url = {https://threatvector.cylance.com/en_us/home/threat-spotlight-neshta-file-infector-endures.html}, language = {English}, urldate = {2021-02-06} } Threat Spotlight: Neshta File Infector Endures
neshta
2014-07-18Virus BulletinRaul Alvarez
@online{alvarez:20140718:birds:9f9e509, author = {Raul Alvarez}, title = {{Bird's nest}}, date = {2014-07-18}, organization = {Virus Bulletin}, url = {https://www.virusbulletin.com/virusbulletin/2014/08/bird-s-nest}, language = {English}, urldate = {2019-11-28} } Bird's nest
neshta
2006-01-15ESET ResearchVirus Radar
@online{radar:20060115:win32neshta:e4ec5b0, author = {Virus Radar}, title = {{Win32/Neshta}}, date = {2006-01-15}, organization = {ESET Research}, url = {https://www.virusradar.com/en/Win32_Neshta.A/description}, language = {English}, urldate = {2019-12-10} } Win32/Neshta
neshta
Yara Rules
[TLP:WHITE] win_neshta_auto (20201014 | autogenerated rule brought to you by yara-signator)
rule win_neshta_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"
        signator_config = "callsandjumps;datarefs;binvalue"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.neshta"
        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 = { 68???????? 64ff30 648920 e8???????? dd5df8 9b 8d45f4 }
            // n = 7, score = 100
            //   68????????           |                     
            //   64ff30               | push                dword ptr fs:[eax]
            //   648920               | mov                 dword ptr fs:[eax], esp
            //   e8????????           |                     
            //   dd5df8               | fstp                qword ptr [ebp - 8]
            //   9b                   | wait                
            //   8d45f4               | lea                 eax, [ebp - 0xc]

        $sequence_1 = { 83c418 6a00 e8???????? 50 807b3c01 0f859e000000 6a00 }
            // n = 7, score = 100
            //   83c418               | add                 esp, 0x18
            //   6a00                 | push                0
            //   e8????????           |                     
            //   50                   | push                eax
            //   807b3c01             | cmp                 byte ptr [ebx + 0x3c], 1
            //   0f859e000000         | jne                 0xa4
            //   6a00                 | push                0

        $sequence_2 = { 55 8bd6 8bc3 e8???????? 59 3bf8 }
            // n = 6, score = 100
            //   55                   | push                ebp
            //   8bd6                 | mov                 edx, esi
            //   8bc3                 | mov                 eax, ebx
            //   e8????????           |                     
            //   59                   | pop                 ecx
            //   3bf8                 | cmp                 edi, eax

        $sequence_3 = { 741f 8d85d0feffff 8bd6 e8???????? 8b85d0feffff }
            // n = 5, score = 100
            //   741f                 | je                  0x21
            //   8d85d0feffff         | lea                 eax, [ebp - 0x130]
            //   8bd6                 | mov                 edx, esi
            //   e8????????           |                     
            //   8b85d0feffff         | mov                 eax, dword ptr [ebp - 0x130]

        $sequence_4 = { 8d45ec 8b4df8 ba???????? e8???????? 8b55ec 58 e8???????? }
            // n = 7, score = 100
            //   8d45ec               | lea                 eax, [ebp - 0x14]
            //   8b4df8               | mov                 ecx, dword ptr [ebp - 8]
            //   ba????????           |                     
            //   e8????????           |                     
            //   8b55ec               | mov                 edx, dword ptr [ebp - 0x14]
            //   58                   | pop                 eax
            //   e8????????           |                     

        $sequence_5 = { 8d55f8 b908000000 e8???????? 33c0 5a }
            // n = 5, score = 100
            //   8d55f8               | lea                 edx, [ebp - 8]
            //   b908000000           | mov                 ecx, 8
            //   e8????????           |                     
            //   33c0                 | xor                 eax, eax
            //   5a                   | pop                 edx

        $sequence_6 = { 8bf8 55 8bd6 8bc3 e8???????? }
            // n = 5, score = 100
            //   8bf8                 | mov                 edi, eax
            //   55                   | push                ebp
            //   8bd6                 | mov                 edx, esi
            //   8bc3                 | mov                 eax, ebx
            //   e8????????           |                     

        $sequence_7 = { e8???????? 8b4dec 33d2 8bc3 e8???????? 8bc3 e8???????? }
            // n = 7, score = 100
            //   e8????????           |                     
            //   8b4dec               | mov                 ecx, dword ptr [ebp - 0x14]
            //   33d2                 | xor                 edx, edx
            //   8bc3                 | mov                 eax, ebx
            //   e8????????           |                     
            //   8bc3                 | mov                 eax, ebx
            //   e8????????           |                     

        $sequence_8 = { 2bf8 8bc1 b990010000 99 f7f9 }
            // n = 5, score = 100
            //   2bf8                 | sub                 edi, eax
            //   8bc1                 | mov                 eax, ecx
            //   b990010000           | mov                 ecx, 0x190
            //   99                   | cdq                 
            //   f7f9                 | idiv                ecx

        $sequence_9 = { 33c9 8a08 41 e8???????? 741f 8d85d0feffff 8bd6 }
            // n = 7, score = 100
            //   33c9                 | xor                 ecx, ecx
            //   8a08                 | mov                 cl, byte ptr [eax]
            //   41                   | inc                 ecx
            //   e8????????           |                     
            //   741f                 | je                  0x21
            //   8d85d0feffff         | lea                 eax, [ebp - 0x130]
            //   8bd6                 | mov                 edx, esi

    condition:
        7 of them and filesize < 229376
}
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