SYMBOLCOMMON_NAMEaka. SYNONYMS
win.maui (Back to overview)

Maui Ransomware

Actor(s): Silent Chollima


There is no description at this point.

References
2022-08-09KasperskyKurt Baumgartner, Seongsu Park
@online{baumgartner:20220809:andariel:89d6b24, author = {Kurt Baumgartner and Seongsu Park}, title = {{Andariel deploys DTrack and Maui ransomware}}, date = {2022-08-09}, organization = {Kaspersky}, url = {https://securelist.com/andariel-deploys-dtrack-and-maui-ransomware/107063/}, language = {English}, urldate = {2022-08-11} } Andariel deploys DTrack and Maui ransomware
Dtrack Maui Ransomware
2022-07-06StairwellSilas Cutler
@techreport{cutler:20220706:maui:1d2ddc2, author = {Silas Cutler}, title = {{Maui Ransomware}}, date = {2022-07-06}, institution = {Stairwell}, url = {https://stairwell.com/wp-content/uploads/2022/07/Stairwell-Threat-Report-Maui-Ransomware.pdf}, language = {English}, urldate = {2022-07-06} } Maui Ransomware
Maui Ransomware
2022-07-06CISAFBI, CISA, Department of the Treasury (Treasury)
@online{fbi:20220706:alert:4231af8, author = {FBI and CISA and Department of the Treasury (Treasury)}, title = {{Alert (AA22-187A): North Korean State-Sponsored Cyber Actors Use Maui Ransomware to Target the Healthcare and Public Health Sector}}, date = {2022-07-06}, organization = {CISA}, url = {https://www.cisa.gov/uscert/ncas/alerts/aa22-187a}, language = {English}, urldate = {2022-07-13} } Alert (AA22-187A): North Korean State-Sponsored Cyber Actors Use Maui Ransomware to Target the Healthcare and Public Health Sector
Maui Ransomware
2022-07-06CISAFBI, CISA, Department of the Treasury (Treasury)
@techreport{fbi:20220706:csa:fcffb49, author = {FBI and CISA and Department of the Treasury (Treasury)}, title = {{CSA AA22-187A: North Korean State-Sponsored Cyber Actors Use Maui Ransomware to Target the Healthcare and Public Health Sector (PDF)}}, date = {2022-07-06}, institution = {CISA}, url = {https://www.cisa.gov/uscert/sites/default/files/publications/aa22-187a-north-korean%20state-sponsored-cyber-actors-use-maui-ransomware-to-target-the-hph-sector.pdf}, language = {English}, urldate = {2022-07-13} } CSA AA22-187A: North Korean State-Sponsored Cyber Actors Use Maui Ransomware to Target the Healthcare and Public Health Sector (PDF)
Maui Ransomware
Yara Rules
[TLP:WHITE] win_maui_auto (20220808 | Detects win.maui.)
rule win_maui_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2022-08-05"
        version = "1"
        description = "Detects win.maui."
        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.maui"
        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 = { 8b7c2428 e9???????? 6838030000 68???????? 68da000000 6a6c 6a0d }
            // n = 7, score = 100
            //   8b7c2428             | mov                 edi, dword ptr [esp + 0x28]
            //   e9????????           |                     
            //   6838030000           | push                0x338
            //   68????????           |                     
            //   68da000000           | push                0xda
            //   6a6c                 | push                0x6c
            //   6a0d                 | push                0xd

        $sequence_1 = { 83ff0d 897c2418 0f8ce2010000 33d2 83fa06 751b 8a041e }
            // n = 7, score = 100
            //   83ff0d               | cmp                 edi, 0xd
            //   897c2418             | mov                 dword ptr [esp + 0x18], edi
            //   0f8ce2010000         | jl                  0x1e8
            //   33d2                 | xor                 edx, edx
            //   83fa06               | cmp                 edx, 6
            //   751b                 | jne                 0x1d
            //   8a041e               | mov                 al, byte ptr [esi + ebx]

        $sequence_2 = { 7530 680c010000 68???????? 688f000000 6a69 6a21 e8???????? }
            // n = 7, score = 100
            //   7530                 | jne                 0x32
            //   680c010000           | push                0x10c
            //   68????????           |                     
            //   688f000000           | push                0x8f
            //   6a69                 | push                0x69
            //   6a21                 | push                0x21
            //   e8????????           |                     

        $sequence_3 = { 85c0 0f8456010000 837c241800 74e0 8b4628 a802 750d }
            // n = 7, score = 100
            //   85c0                 | test                eax, eax
            //   0f8456010000         | je                  0x15c
            //   837c241800           | cmp                 dword ptr [esp + 0x18], 0
            //   74e0                 | je                  0xffffffe2
            //   8b4628               | mov                 eax, dword ptr [esi + 0x28]
            //   a802                 | test                al, 2
            //   750d                 | jne                 0xf

        $sequence_4 = { 8bec 5d e9???????? 8bff 55 8bec 81ec54020000 }
            // n = 7, score = 100
            //   8bec                 | mov                 ebp, esp
            //   5d                   | pop                 ebp
            //   e9????????           |                     
            //   8bff                 | mov                 edi, edi
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp
            //   81ec54020000         | sub                 esp, 0x254

        $sequence_5 = { 55 56 56 e8???????? 83c414 85c0 7446 }
            // n = 7, score = 100
            //   55                   | push                ebp
            //   56                   | push                esi
            //   56                   | push                esi
            //   e8????????           |                     
            //   83c414               | add                 esp, 0x14
            //   85c0                 | test                eax, eax
            //   7446                 | je                  0x48

        $sequence_6 = { 83c418 89442414 85c0 751a 68a9010000 68???????? 6a03 }
            // n = 7, score = 100
            //   83c418               | add                 esp, 0x18
            //   89442414             | mov                 dword ptr [esp + 0x14], eax
            //   85c0                 | test                eax, eax
            //   751a                 | jne                 0x1c
            //   68a9010000           | push                0x1a9
            //   68????????           |                     
            //   6a03                 | push                3

        $sequence_7 = { 8d4900 8b8c24bc000000 8b542414 8b442420 51 52 }
            // n = 6, score = 100
            //   8d4900               | lea                 ecx, [ecx]
            //   8b8c24bc000000       | mov                 ecx, dword ptr [esp + 0xbc]
            //   8b542414             | mov                 edx, dword ptr [esp + 0x14]
            //   8b442420             | mov                 eax, dword ptr [esp + 0x20]
            //   51                   | push                ecx
            //   52                   | push                edx

        $sequence_8 = { 8b442424 332cbdd0a94800 8bcb 33680c c1e908 81e1ff000000 8b0c8dd0a54800 }
            // n = 7, score = 100
            //   8b442424             | mov                 eax, dword ptr [esp + 0x24]
            //   332cbdd0a94800       | xor                 ebp, dword ptr [edi*4 + 0x48a9d0]
            //   8bcb                 | mov                 ecx, ebx
            //   33680c               | xor                 ebp, dword ptr [eax + 0xc]
            //   c1e908               | shr                 ecx, 8
            //   81e1ff000000         | and                 ecx, 0xff
            //   8b0c8dd0a54800       | mov                 ecx, dword ptr [ecx*4 + 0x48a5d0]

        $sequence_9 = { c7475800000000 e8???????? 8b0f 8b442430 8808 40 8bd1 }
            // n = 7, score = 100
            //   c7475800000000       | mov                 dword ptr [edi + 0x58], 0
            //   e8????????           |                     
            //   8b0f                 | mov                 ecx, dword ptr [edi]
            //   8b442430             | mov                 eax, dword ptr [esp + 0x30]
            //   8808                 | mov                 byte ptr [eax], cl
            //   40                   | inc                 eax
            //   8bd1                 | mov                 edx, ecx

    condition:
        7 of them and filesize < 1616896
}
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