Actor(s): Tick
There is no description at this point.
rule win_xxmm_auto { meta: author = "Felix Bilstein - yara-signator at cocacoding dot com" date = "2024-10-31" version = "1" description = "Detects win.xxmm." 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.xxmm" malpedia_rule_date = "20241030" malpedia_hash = "26e26953c49c8efafbf72a38076855d578e0a2e4" malpedia_version = "20241030" 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 = { 85c9 7451 53 56 57 } // n = 5, score = 600 // 85c9 | test ecx, ecx // 7451 | je 0x53 // 53 | push ebx // 56 | push esi // 57 | push edi $sequence_1 = { 0fb6d2 7206 8d7c17e0 eb02 } // n = 4, score = 600 // 0fb6d2 | movzx edx, dl // 7206 | jb 8 // 8d7c17e0 | lea edi, [edi + edx - 0x20] // eb02 | jmp 4 $sequence_2 = { 8b4c111c 8d0481 8b0410 03c2 eb12 8b07 } // n = 6, score = 600 // 8b4c111c | mov ecx, dword ptr [ecx + edx + 0x1c] // 8d0481 | lea eax, [ecx + eax*4] // 8b0410 | mov eax, dword ptr [eax + edx] // 03c2 | add eax, edx // eb12 | jmp 0x14 // 8b07 | mov eax, dword ptr [edi] $sequence_3 = { 4f 81cf00ffffff 47 8d040f 0fb610 035510 81e2ff000080 } // n = 7, score = 600 // 4f | dec edi // 81cf00ffffff | or edi, 0xffffff00 // 47 | inc edi // 8d040f | lea eax, [edi + ecx] // 0fb610 | movzx edx, byte ptr [eax] // 035510 | add edx, dword ptr [ebp + 0x10] // 81e2ff000080 | and edx, 0x800000ff $sequence_4 = { e8???????? 8d1c07 8b7320 8bcf e8???????? } // n = 5, score = 600 // e8???????? | // 8d1c07 | lea ebx, [edi + eax] // 8b7320 | mov esi, dword ptr [ebx + 0x20] // 8bcf | mov ecx, edi // e8???????? | $sequence_5 = { 5b c3 53 8d5804 e8???????? ff33 } // n = 6, score = 600 // 5b | pop ebx // c3 | ret // 53 | push ebx // 8d5804 | lea ebx, [eax + 4] // e8???????? | // ff33 | push dword ptr [ebx] $sequence_6 = { 8b440878 8b7c0820 8b540824 03f9 03d1 8955f8 } // n = 6, score = 600 // 8b440878 | mov eax, dword ptr [eax + ecx + 0x78] // 8b7c0820 | mov edi, dword ptr [eax + ecx + 0x20] // 8b540824 | mov edx, dword ptr [eax + ecx + 0x24] // 03f9 | add edi, ecx // 03d1 | add edx, ecx // 8955f8 | mov dword ptr [ebp - 8], edx $sequence_7 = { 0f8481000000 8b96a0000000 0355f8 8b4204 } // n = 4, score = 600 // 0f8481000000 | je 0x87 // 8b96a0000000 | mov edx, dword ptr [esi + 0xa0] // 0355f8 | add edx, dword ptr [ebp - 8] // 8b4204 | mov eax, dword ptr [edx + 4] $sequence_8 = { 8b540e1c 8d0482 03c1 81fb8e4e0eec 7509 8b00 03c1 } // n = 7, score = 600 // 8b540e1c | mov edx, dword ptr [esi + ecx + 0x1c] // 8d0482 | lea eax, [edx + eax*4] // 03c1 | add eax, ecx // 81fb8e4e0eec | cmp ebx, 0xec0e4e8e // 7509 | jne 0xb // 8b00 | mov eax, dword ptr [eax] // 03c1 | add eax, ecx $sequence_9 = { 47 8d040f 0fb610 035510 } // n = 4, score = 600 // 47 | inc edi // 8d040f | lea eax, [edi + ecx] // 0fb610 | movzx edx, byte ptr [eax] // 035510 | add edx, dword ptr [ebp + 0x10] condition: 7 of them and filesize < 540672 }
rule win_xxmm_w0 { meta: author = "Florian Roth" description = "Detects malware / hacktool sample from Bronze Butler incident" malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.xxmm" malpedia_version = "20180301" malpedia_license = "CC BY-NC-SA 4.0" malpedia_sharing = "TLP:WHITE" strings: $x1 = "\\Release\\ReflectivLoader.pdb" ascii $x3 = "\\Projects\\xxmm2\\Release\\" ascii $x5 = "http://127.0.0.1/phptunnel.php" fullword ascii $s1 = "xxmm2.exe" fullword ascii $s2 = "\\AvUpdate.exe" fullword wide $s3 = "stdapi_fs_file_download" fullword ascii $s4 = "stdapi_syncshell_open" fullword ascii $s5 = "stdapi_execute_sleep" fullword ascii $s6 = "stdapi_syncshell_kill" fullword ascii condition: 1 of ($x*) or 4 of them }
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