SYMBOLCOMMON_NAMEaka. SYNONYMS
win.milum (Back to overview)

Milum


In August 2019, Kaspersky Labs discovered a malware they dubbed Milum (naming based on internal file name fragments) when investigating an operation they named WildPressure. It is written in C++ using STL, primarily to parse JSON. Functionality includes bidirectional file transmission and remote command execution.

References
2021-07-07KasperskyDenis Legezo
@online{legezo:20210707:wildpressure:0bdf5ef, author = {Denis Legezo}, title = {{WildPressure targets the macOS platform}}, date = {2021-07-07}, organization = {Kaspersky}, url = {https://securelist.com/wildpressure-targets-macos/103072/}, language = {English}, urldate = {2021-07-09} } WildPressure targets the macOS platform
Guard Milum
2020-09-24Kaspersky LabsKaspersky Lab ICS CERT
@techreport{cert:20200924:threat:2d7986d, author = {Kaspersky Lab ICS CERT}, title = {{Threat landscape for industrial automation systems - H1 2020}}, date = {2020-09-24}, institution = {Kaspersky Labs}, url = {https://ics-cert.kaspersky.com/media/KASPERSKY_H1_2020_ICS_REPORT_EN.pdf}, language = {English}, urldate = {2020-10-04} } Threat landscape for industrial automation systems - H1 2020
Poet RAT Mailto Milum RagnarLocker REvil Ryuk Snake
2020-03-24Kaspersky LabsDenis Legezo
@online{legezo:20200324:wildpressure:add6905, author = {Denis Legezo}, title = {{WildPressure targets industrial-related entities in the Middle East}}, date = {2020-03-24}, organization = {Kaspersky Labs}, url = {https://securelist.com/wildpressure-targets-industrial-in-the-middle-east/96360/}, language = {English}, urldate = {2020-03-26} } WildPressure targets industrial-related entities in the Middle East
Milum
Yara Rules
[TLP:WHITE] win_milum_auto (20220808 | Detects win.milum.)
rule win_milum_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2022-08-05"
        version = "1"
        description = "Detects win.milum."
        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.milum"
        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 = { 33c9 0fb61401 41 894df4 8b4e24 8955e4 85c9 }
            // n = 7, score = 400
            //   33c9                 | xor                 ecx, ecx
            //   0fb61401             | movzx               edx, byte ptr [ecx + eax]
            //   41                   | inc                 ecx
            //   894df4               | mov                 dword ptr [ebp - 0xc], ecx
            //   8b4e24               | mov                 ecx, dword ptr [esi + 0x24]
            //   8955e4               | mov                 dword ptr [ebp - 0x1c], edx
            //   85c9                 | test                ecx, ecx

        $sequence_1 = { 8d4dc0 891e 895e04 895e08 3bf1 741e 8b45c4 }
            // n = 7, score = 400
            //   8d4dc0               | lea                 ecx, [ebp - 0x40]
            //   891e                 | mov                 dword ptr [esi], ebx
            //   895e04               | mov                 dword ptr [esi + 4], ebx
            //   895e08               | mov                 dword ptr [esi + 8], ebx
            //   3bf1                 | cmp                 esi, ecx
            //   741e                 | je                  0x20
            //   8b45c4               | mov                 eax, dword ptr [ebp - 0x3c]

        $sequence_2 = { 89b520ffffff 899d1cffffff 889d0cffffff e8???????? c645fc0d 6aff 53 }
            // n = 7, score = 400
            //   89b520ffffff         | mov                 dword ptr [ebp - 0xe0], esi
            //   899d1cffffff         | mov                 dword ptr [ebp - 0xe4], ebx
            //   889d0cffffff         | mov                 byte ptr [ebp - 0xf4], bl
            //   e8????????           |                     
            //   c645fc0d             | mov                 byte ptr [ebp - 4], 0xd
            //   6aff                 | push                -1
            //   53                   | push                ebx

        $sequence_3 = { 7415 83f867 7410 83f871 740b 3d9a020000 0f85aa080000 }
            // n = 7, score = 400
            //   7415                 | je                  0x17
            //   83f867               | cmp                 eax, 0x67
            //   7410                 | je                  0x12
            //   83f871               | cmp                 eax, 0x71
            //   740b                 | je                  0xd
            //   3d9a020000           | cmp                 eax, 0x29a
            //   0f85aa080000         | jne                 0x8b0

        $sequence_4 = { 41 ff4df0 894de8 c74604483f0000 e9???????? 837e0c00 0f84c7000000 }
            // n = 7, score = 400
            //   41                   | inc                 ecx
            //   ff4df0               | dec                 dword ptr [ebp - 0x10]
            //   894de8               | mov                 dword ptr [ebp - 0x18], ecx
            //   c74604483f0000       | mov                 dword ptr [esi + 4], 0x3f48
            //   e9????????           |                     
            //   837e0c00             | cmp                 dword ptr [esi + 0xc], 0
            //   0f84c7000000         | je                  0xcd

        $sequence_5 = { 68ff030000 6a00 8d85edfbffff 50 e8???????? 83c40c 8bb550fbffff }
            // n = 7, score = 400
            //   68ff030000           | push                0x3ff
            //   6a00                 | push                0
            //   8d85edfbffff         | lea                 eax, [ebp - 0x413]
            //   50                   | push                eax
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc
            //   8bb550fbffff         | mov                 esi, dword ptr [ebp - 0x4b0]

        $sequence_6 = { 33c5 50 8d45f4 64a300000000 8b4d0c 2b0e b893244992 }
            // n = 7, score = 400
            //   33c5                 | xor                 eax, ebp
            //   50                   | push                eax
            //   8d45f4               | lea                 eax, [ebp - 0xc]
            //   64a300000000         | mov                 dword ptr fs:[0], eax
            //   8b4d0c               | mov                 ecx, dword ptr [ebp + 0xc]
            //   2b0e                 | sub                 ecx, dword ptr [esi]
            //   b893244992           | mov                 eax, 0x92492493

        $sequence_7 = { 6a08 6a0f 6a08 52 50 e8???????? 83c420 }
            // n = 7, score = 400
            //   6a08                 | push                8
            //   6a0f                 | push                0xf
            //   6a08                 | push                8
            //   52                   | push                edx
            //   50                   | push                eax
            //   e8????????           |                     
            //   83c420               | add                 esp, 0x20

        $sequence_8 = { c645fc02 83c204 8955d0 8b4304 3bf8 736d 8b13 }
            // n = 7, score = 400
            //   c645fc02             | mov                 byte ptr [ebp - 4], 2
            //   83c204               | add                 edx, 4
            //   8955d0               | mov                 dword ptr [ebp - 0x30], edx
            //   8b4304               | mov                 eax, dword ptr [ebx + 4]
            //   3bf8                 | cmp                 edi, eax
            //   736d                 | jae                 0x6f
            //   8b13                 | mov                 edx, dword ptr [ebx]

        $sequence_9 = { 5d c20400 8bc8 c1e909 f6c101 7419 }
            // n = 6, score = 400
            //   5d                   | pop                 ebp
            //   c20400               | ret                 4
            //   8bc8                 | mov                 ecx, eax
            //   c1e909               | shr                 ecx, 9
            //   f6c101               | test                cl, 1
            //   7419                 | je                  0x1b

    condition:
        7 of them and filesize < 1076224
}
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