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 = "2023-01-25" 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 = "20230124" malpedia_hash = "2ee0eebba83dce3d019a90519f2f972c0fcf9686" malpedia_version = "20230125" 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 = { 8945e0 eb20 81fb54caaf91 7509 8b00 03c1 8945ec } // n = 7, score = 600 // 8945e0 | mov dword ptr [ebp - 0x20], eax // eb20 | jmp 0x22 // 81fb54caaf91 | cmp ebx, 0x91afca54 // 7509 | jne 0xb // 8b00 | mov eax, dword ptr [eax] // 03c1 | add eax, ecx // 8945ec | mov dword ptr [ebp - 0x14], eax $sequence_1 = { 740b 2bfb 8a11 88140f } // n = 4, score = 600 // 740b | je 0xd // 2bfb | sub edi, ebx // 8a11 | mov dl, byte ptr [ecx] // 88140f | mov byte ptr [edi + ecx], dl $sequence_2 = { 8b440e24 03f9 03c1 8945f8 c745f404000000 8b07 03c1 } // n = 7, score = 600 // 8b440e24 | mov eax, dword ptr [esi + ecx + 0x24] // 03f9 | add edi, ecx // 03c1 | add eax, ecx // 8945f8 | mov dword ptr [ebp - 8], eax // c745f404000000 | mov dword ptr [ebp - 0xc], 4 // 8b07 | mov eax, dword ptr [edi] // 03c1 | add eax, ecx $sequence_3 = { 8bd9 894c2420 741c 48 } // n = 4, score = 600 // 8bd9 | mov ebx, ecx // 894c2420 | mov dword ptr [esp + 0x20], ecx // 741c | je 0x1e // 48 | dec eax $sequence_4 = { 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_5 = { 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_6 = { 8945e0 8b45f4 0fb700 668bf8 } // n = 4, score = 600 // 8945e0 | mov dword ptr [ebp - 0x20], eax // 8b45f4 | mov eax, dword ptr [ebp - 0xc] // 0fb700 | movzx eax, word ptr [eax] // 668bf8 | mov di, ax $sequence_7 = { 752b 33c9 ff15???????? b801000000 48 83c428 } // n = 6, score = 600 // 752b | jne 0x2d // 33c9 | xor ecx, ecx // ff15???????? | // b801000000 | mov eax, 1 // 48 | dec eax // 83c428 | add esp, 0x28 $sequence_8 = { 8b5dfc 83c728 837de800 75d7 8b9e80000000 } // n = 5, score = 600 // 8b5dfc | mov ebx, dword ptr [ebp - 4] // 83c728 | add edi, 0x28 // 837de800 | cmp dword ptr [ebp - 0x18], 0 // 75d7 | jne 0xffffffd9 // 8b9e80000000 | mov ebx, dword ptr [esi + 0x80] $sequence_9 = { 03c1 81fb8e4e0eec 7509 8b00 03c1 } // n = 5, score = 600 // 03c1 | add eax, ecx // 81fb8e4e0eec | cmp ebx, 0xec0e4e8e // 7509 | jne 0xb // 8b00 | mov eax, dword ptr [eax] // 03c1 | add eax, ecx 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 }
If your designated proposal does not fit in any other category, feel free to write a free-text in the comment field below.
Please propose all changes regarding references on the Malpedia library page
Your suggestion will be reviewed before being published. Thank you for contributing!
YYYY-MM-DD
YYYY-MM
YYYY