rule win_rifdoor_auto { meta: author = "Felix Bilstein - yara-signator at cocacoding dot com" date = "2026-09-17" version = "1" description = "Detects win.rifdoor." 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.rifdoor" malpedia_rule_date = "20260916" malpedia_hash = "53a643781c18e08f4a50949af60172d837a0b6f6" malpedia_version = "20260917" 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 = { 3bf7 7cc8 5b 8bc6 5e 5d 59 } // n = 7, score = 200 // 3bf7 | cmp esi, edi // 7cc8 | jl 0xffffffca // 5b | pop ebx // 8bc6 | mov eax, esi // 5e | pop esi // 5d | pop ebp // 59 | pop ecx $sequence_1 = { b940000000 32db 3bc1 7d0e 885c301c 017e5c 8b465c } // n = 7, score = 200 // b940000000 | mov ecx, 0x40 // 32db | xor bl, bl // 3bc1 | cmp eax, ecx // 7d0e | jge 0x10 // 885c301c | mov byte ptr [eax + esi + 0x1c], bl // 017e5c | add dword ptr [esi + 0x5c], edi // 8b465c | mov eax, dword ptr [esi + 0x5c] $sequence_2 = { e8???????? 83c40c 55 57 ffd6 a3???????? 895c2410 } // n = 7, score = 200 // e8???????? | // 83c40c | add esp, 0xc // 55 | push ebp // 57 | push edi // ffd6 | call esi // a3???????? | // 895c2410 | mov dword ptr [esp + 0x10], ebx $sequence_3 = { 33c9 8b540c2c 3b91541d4100 7513 83e804 83c104 83f804 } // n = 7, score = 200 // 33c9 | xor ecx, ecx // 8b540c2c | mov edx, dword ptr [esp + ecx + 0x2c] // 3b91541d4100 | cmp edx, dword ptr [ecx + 0x411d54] // 7513 | jne 0x15 // 83e804 | sub eax, 4 // 83c104 | add ecx, 4 // 83f804 | cmp eax, 4 $sequence_4 = { 8d442410 50 8d4314 b9???????? 895c2414 e8???????? } // n = 6, score = 200 // 8d442410 | lea eax, [esp + 0x10] // 50 | push eax // 8d4314 | lea eax, [ebx + 0x14] // b9???????? | // 895c2414 | mov dword ptr [esp + 0x14], ebx // e8???????? | $sequence_5 = { 75f1 8d442404 6a12 50 e8???????? } // n = 5, score = 200 // 75f1 | jne 0xfffffff3 // 8d442404 | lea eax, [esp + 4] // 6a12 | push 0x12 // 50 | push eax // e8???????? | $sequence_6 = { c744241801000000 8d542410 52 b810000000 } // n = 4, score = 200 // c744241801000000 | mov dword ptr [esp + 0x18], 1 // 8d542410 | lea edx, [esp + 0x10] // 52 | push edx // b810000000 | mov eax, 0x10 $sequence_7 = { 83f93d 7468 83f920 7505 b92b000000 0fbf0c4db81d4100 } // n = 6, score = 200 // 83f93d | cmp ecx, 0x3d // 7468 | je 0x6a // 83f920 | cmp ecx, 0x20 // 7505 | jne 7 // b92b000000 | mov ecx, 0x2b // 0fbf0c4db81d4100 | movsx ecx, word ptr [ecx*2 + 0x411db8] $sequence_8 = { 52 8d45e8 50 8d8de8f7ffff } // n = 4, score = 100 // 52 | push edx // 8d45e8 | lea eax, [ebp - 0x18] // 50 | push eax // 8d8de8f7ffff | lea ecx, [ebp - 0x818] $sequence_9 = { 83c40c 8d8d68fcffff 51 8d9574fcffff 52 6a00 } // n = 6, score = 100 // 83c40c | add esp, 0xc // 8d8d68fcffff | lea ecx, [ebp - 0x398] // 51 | push ecx // 8d9574fcffff | lea edx, [ebp - 0x38c] // 52 | push edx // 6a00 | push 0 $sequence_10 = { 83c103 51 ffd3 a3???????? eb2c 8b14b7 83c203 } // n = 7, score = 100 // 83c103 | add ecx, 3 // 51 | push ecx // ffd3 | call ebx // a3???????? | // eb2c | jmp 0x2e // 8b14b7 | mov edx, dword ptr [edi + esi*4] // 83c203 | add edx, 3 $sequence_11 = { 68ff000000 e8???????? 59 59 8b7508 8d34f5000d4100 391e } // n = 7, score = 100 // 68ff000000 | push 0xff // e8???????? | // 59 | pop ecx // 59 | pop ecx // 8b7508 | mov esi, dword ptr [ebp + 8] // 8d34f5000d4100 | lea esi, [esi*8 + 0x410d00] // 391e | cmp dword ptr [esi], ebx $sequence_12 = { b9843a0000 81fb843a0000 7702 8bcb 2bd9 be2c1a0000 33ff } // n = 7, score = 100 // b9843a0000 | mov ecx, 0x3a84 // 81fb843a0000 | cmp ebx, 0x3a84 // 7702 | ja 4 // 8bcb | mov ecx, ebx // 2bd9 | sub ebx, ecx // be2c1a0000 | mov esi, 0x1a2c // 33ff | xor edi, edi $sequence_13 = { eb08 ff15???????? 33c9 b873b2e745 f72d???????? } // n = 5, score = 100 // eb08 | jmp 0xa // ff15???????? | // 33c9 | xor ecx, ecx // b873b2e745 | mov eax, 0x45e7b273 // f72d???????? | $sequence_14 = { ff15???????? 8bf8 83ffff 0f84bb000000 53 } // n = 5, score = 100 // ff15???????? | // 8bf8 | mov edi, eax // 83ffff | cmp edi, -1 // 0f84bb000000 | je 0xc1 // 53 | push ebx $sequence_15 = { c785e4bcffff44000000 899d1cbdffff c78510bdffff01010000 66898514bdffff 33f6 8d642400 8d8d40bdffff } // n = 7, score = 100 // c785e4bcffff44000000 | mov dword ptr [ebp - 0x431c], 0x44 // 899d1cbdffff | mov dword ptr [ebp - 0x42e4], ebx // c78510bdffff01010000 | mov dword ptr [ebp - 0x42f0], 0x101 // 66898514bdffff | mov word ptr [ebp - 0x42ec], ax // 33f6 | xor esi, esi // 8d642400 | lea esp, [esp] // 8d8d40bdffff | lea ecx, [ebp - 0x42c0] condition: 7 of them and filesize < 212992 }