win.crosswalk (Back to overview)

CROSSWALK

Actor(s): APT41


According to FireEye, CROSSWALK is a skeletal, modular backdoor capable of system survey and adding modules in response to C&C replies.

References
2019-09-04 ⋅ vmwareScott Knight
@online{knight:20190904:cb:a21cf30, author = {Scott Knight}, title = {{CB TAU Threat Intelligence Notification: State-Sponsored Espionage Group Targeting Multiple Verticals with ‘Crosswalk’}}, date = {2019-09-04}, organization = {vmware}, url = {https://www.carbonblack.com/2019/09/04/cb-tau-threat-intelligence-notification-state-sponsored-espionage-group-targeting-multiple-verticals-with-crosswalk/}, language = {English}, urldate = {2020-01-05} } CB TAU Threat Intelligence Notification: State-Sponsored Espionage Group Targeting Multiple Verticals with ‘Crosswalk’
CROSSWALK
2019-08-09 ⋅ FireEyeFireEye
@online{fireeye:20190809:double:40f736e, author = {FireEye}, title = {{Double Dragon APT41, a dual espionage and cyber crime operation}}, date = {2019-08-09}, organization = {FireEye}, url = {https://content.fireeye.com/apt-41/rpt-apt41/}, language = {English}, urldate = {2019-12-18} } Double Dragon APT41, a dual espionage and cyber crime operation
CLASSFON crackshot CROSSWALK GEARSHIFT HIGHNOON HIGHNOON.BIN JUMPALL poisonplug Winnti
2018-12-24 ⋅ Twitter (@MrDanPerez)Dan Perez
@online{perez:20181224:hashes:9a4fc8c, author = {Dan Perez}, title = {{Tweet on hashes for CROSSWALK}}, date = {2018-12-24}, organization = {Twitter (@MrDanPerez)}, url = {https://twitter.com/MrDanPerez/status/1159459082534825986}, language = {English}, urldate = {2019-11-27} } Tweet on hashes for CROSSWALK
CROSSWALK
Yara Rules
[TLP:WHITE] win_crosswalk_auto (20190204 | autogenerated rule brought to you by yara-signator)
rule win_crosswalk_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2019-11-26"
        version = "1"
        description = "autogenerated rule brought to you by yara-signator"
        tool = "yara-signator 0.1a"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.crosswalk"
        malpedia_version = "20190204"
        malpedia_license = "CC BY-NC-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 / approach will be published in the near future 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 = { 81fea0264100 7418 8b86b0000000 85c0 }
            // n = 4, score = 200
            //   81fea0264100         | cmp                 esi, 0x4126a0
            //   7418                 | je                  0x1a
            //   8b86b0000000         | mov                 eax, dword ptr [esi + 0xb0]
            //   85c0                 | test                eax, eax

        $sequence_1 = { 03148d808e4100 8b00 894218 8a03 884228 8b45fc }
            // n = 6, score = 200
            //   03148d808e4100       | add                 edx, dword ptr [ecx*4 + 0x418e80]
            //   8b00                 | mov                 eax, dword ptr [eax]
            //   894218               | mov                 dword ptr [edx + 0x18], eax
            //   8a03                 | mov                 al, byte ptr [ebx]
            //   884228               | mov                 byte ptr [edx + 0x28], al
            //   8b45fc               | mov                 eax, dword ptr [ebp - 4]

        $sequence_2 = { 6804134100 6a04 e8???????? 8bf0 }
            // n = 4, score = 200
            //   6804134100           | push                0x411304
            //   6a04                 | push                4
            //   e8????????           |                     
            //   8bf0                 | mov                 esi, eax

        $sequence_3 = { c3 6874224100 686c224100 6874224100 6a01 }
            // n = 5, score = 200
            //   c3                   | ret                 
            //   6874224100           | push                0x412274
            //   686c224100           | push                0x41226c
            //   6874224100           | push                0x412274
            //   6a01                 | push                1

        $sequence_4 = { 56 33f6 8b86808e4100 85c0 740e }
            // n = 5, score = 200
            //   56                   | push                esi
            //   33f6                 | xor                 esi, esi
            //   8b86808e4100         | mov                 eax, dword ptr [esi + 0x418e80]
            //   85c0                 | test                eax, eax
            //   740e                 | je                  0x10

        $sequence_5 = { 8bd7 c1fa06 8bc7 83e03f 6bc830 8b0495808e4100 f644082801 }
            // n = 7, score = 200
            //   8bd7                 | mov                 edx, edi
            //   c1fa06               | sar                 edx, 6
            //   8bc7                 | mov                 eax, edi
            //   83e03f               | and                 eax, 0x3f
            //   6bc830               | imul                ecx, eax, 0x30
            //   8b0495808e4100       | mov                 eax, dword ptr [edx*4 + 0x418e80]
            //   f644082801           | test                byte ptr [eax + ecx + 0x28], 1

        $sequence_6 = { 6894224100 688c224100 68d4124100 6a04 e8???????? 83c410 }
            // n = 6, score = 200
            //   6894224100           | push                0x412294
            //   688c224100           | push                0x41228c
            //   68d4124100           | push                0x4112d4
            //   6a04                 | push                4
            //   e8????????           |                     
            //   83c410               | add                 esp, 0x10

        $sequence_7 = { 6884584100 83600400 e9???????? 8d4508 50 e8???????? 59 }
            // n = 7, score = 200
            //   6884584100           | push                0x415884
            //   83600400             | and                 dword ptr [eax + 4], 0
            //   e9????????           |                     
            //   8d4508               | lea                 eax, [ebp + 8]
            //   50                   | push                eax
            //   e8????????           |                     
            //   59                   | pop                 ecx

        $sequence_8 = { 83e809 83f806 0f8722ffffff 39771c 0f8519ffffff }
            // n = 5, score = 100
            //   83e809               | dec                 eax
            //   83f806               | cmp                 ecx, edx
            //   0f8722ffffff         | jae                 9
            //   39771c               | sub                 eax, 9
            //   0f8519ffffff         | cmp                 eax, 6

        $sequence_9 = { 488bd0 48d3ca 4933d0 4b8794fe40600100 eb2d }
            // n = 5, score = 100
            //   488bd0               | mov                 edx, 0x80000000
            //   48d3ca               | cmp                 dword ptr [edi + 4], esi
            //   4933d0               | jle                 0xffffff88
            //   4b8794fe40600100     | cmp                 dword ptr [edi], ebp
            //   eb2d                 | jne                 0xffffff88

        $sequence_10 = { 0f8ec4000000 396c2430 0f85ba000000 48634704 85c0 0f8eae000000 392f }
            // n = 7, score = 100
            //   0f8ec4000000         | jmp                 0x2f
            //   396c2430             | mov                 eax, dword ptr [edi + 4]
            //   0f85ba000000         | cmp                 dword ptr [esp + 0x30], eax
            //   48634704             | jne                 0x50
            //   85c0                 | dec                 eax
            //   0f8eae000000         | mov                 ecx, ebx
            //   392f                 | sar                 edx, 0xb

        $sequence_11 = { 448d4607 33c0 4533c9 4821442430 ba00000080 }
            // n = 5, score = 100
            //   448d4607             | ja                  0xffffff28
            //   33c0                 | cmp                 dword ptr [edi + 0x1c], esi
            //   4533c9               | jne                 0xffffff28
            //   4821442430           | inc                 esp
            //   ba00000080           | lea                 eax, [esi + 7]

        $sequence_12 = { 397704 7e83 392f 0f857bffffff 8b4f0c }
            // n = 5, score = 100
            //   397704               | xor                 eax, eax
            //   7e83                 | inc                 ebp
            //   392f                 | xor                 ecx, ecx
            //   0f857bffffff         | dec                 eax
            //   8b4f0c               | and                 dword ptr [esp + 0x30], eax

        $sequence_13 = { c1fa0b 8bc2 c1e81f 03d0 69c2890e0000 }
            // n = 5, score = 100
            //   c1fa0b               | ror                 edx, cl
            //   8bc2                 | dec                 ecx
            //   c1e81f               | xor                 edx, eax
            //   03d0                 | dec                 ebx
            //   69c2890e0000         | xchg                dword ptr [esi + edi*8 + 0x16040], edx

        $sequence_14 = { 8b4704 39442430 7545 488bcb }
            // n = 4, score = 100
            //   8b4704               | mov                 ecx, dword ptr [edi + 0xc]
            //   39442430             | dec                 eax
            //   7545                 | mov                 edx, eax
            //   488bcb               | dec                 eax

        $sequence_15 = { 488d05???????? eb04 4883c020 4883c428 c3 483bca 7304 }
            // n = 7, score = 100
            //   488d05????????       |                     
            //   eb04                 | jmp                 6
            //   4883c020             | dec                 eax
            //   4883c428             | add                 eax, 0x20
            //   c3                   | dec                 eax
            //   483bca               | add                 esp, 0x28
            //   7304                 | ret                 

    condition:
        7 of them
}
Download all Yara Rules