rule win_elise_auto { meta: author = "Felix Bilstein - yara-signator at cocacoding dot com" date = "2026-09-17" version = "1" description = "Detects win.elise." 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.elise" 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 = { 6a01 8bd3 e8???????? 0fb6c0 8b4f44 8b573c 33f6 } // n = 7, score = 400 // 6a01 | push 1 // 8bd3 | mov edx, ebx // e8???????? | // 0fb6c0 | movzx eax, al // 8b4f44 | mov ecx, dword ptr [edi + 0x44] // 8b573c | mov edx, dword ptr [edi + 0x3c] // 33f6 | xor esi, esi $sequence_1 = { 33c9 888f00010000 888f01010000 8bf7 } // n = 4, score = 400 // 33c9 | xor ecx, ecx // 888f00010000 | mov byte ptr [edi + 0x100], cl // 888f01010000 | mov byte ptr [edi + 0x101], cl // 8bf7 | mov esi, edi $sequence_2 = { ff4c2410 8d7c7e01 75cf 8bc7 5f } // n = 5, score = 400 // ff4c2410 | dec dword ptr [esp + 0x10] // 8d7c7e01 | lea edi, [esi + edi*2 + 1] // 75cf | jne 0xffffffd1 // 8bc7 | mov eax, edi // 5f | pop edi $sequence_3 = { c20400 55 8bec 51 8309ff 8b4108 53 } // n = 7, score = 400 // c20400 | ret 4 // 55 | push ebp // 8bec | mov ebp, esp // 51 | push ecx // 8309ff | or dword ptr [ecx], 0xffffffff // 8b4108 | mov eax, dword ptr [ecx + 8] // 53 | push ebx $sequence_4 = { 0bc5 8bcb 8dbe06050000 f3ab } // n = 4, score = 400 // 0bc5 | or eax, ebp // 8bcb | mov ecx, ebx // 8dbe06050000 | lea edi, [esi + 0x506] // f3ab | rep stosd dword ptr es:[edi], eax $sequence_5 = { 03c6 50 e8???????? 03c6 4f } // n = 5, score = 400 // 03c6 | add eax, esi // 50 | push eax // e8???????? | // 03c6 | add eax, esi // 4f | dec edi $sequence_6 = { 735a 3b4614 7606 807e1c00 744f 43 33c9 } // n = 7, score = 400 // 735a | jae 0x5c // 3b4614 | cmp eax, dword ptr [esi + 0x14] // 7606 | jbe 8 // 807e1c00 | cmp byte ptr [esi + 0x1c], 0 // 744f | je 0x51 // 43 | inc ebx // 33c9 | xor ecx, ecx $sequence_7 = { 8b690c 56 57 85ed 7440 8b4118 83787800 } // n = 7, score = 400 // 8b690c | mov ebp, dword ptr [ecx + 0xc] // 56 | push esi // 57 | push edi // 85ed | test ebp, ebp // 7440 | je 0x42 // 8b4118 | mov eax, dword ptr [ecx + 0x18] // 83787800 | cmp dword ptr [eax + 0x78], 0 $sequence_8 = { e8???????? 837df804 7306 8365f800 eb10 } // n = 5, score = 400 // e8???????? | // 837df804 | cmp dword ptr [ebp - 8], 4 // 7306 | jae 8 // 8365f800 | and dword ptr [ebp - 8], 0 // eb10 | jmp 0x12 $sequence_9 = { 7908 4b 81cb00ffffff 43 0fb6fb 8a1c07 8b7df0 } // n = 7, score = 300 // 7908 | jns 0xa // 4b | dec ebx // 81cb00ffffff | or ebx, 0xffffff00 // 43 | inc ebx // 0fb6fb | movzx edi, bl // 8a1c07 | mov bl, byte ptr [edi + eax] // 8b7df0 | mov edi, dword ptr [ebp - 0x10] $sequence_10 = { ff45f8 8b7df8 3b7d0c 0f8c7bffffff 5f } // n = 5, score = 300 // ff45f8 | inc dword ptr [ebp - 8] // 8b7df8 | mov edi, dword ptr [ebp - 8] // 3b7d0c | cmp edi, dword ptr [ebp + 0xc] // 0f8c7bffffff | jl 0xffffff81 // 5f | pop edi $sequence_11 = { 85f6 7507 33c0 e9???????? 833d????????00 } // n = 5, score = 300 // 85f6 | test esi, esi // 7507 | jne 9 // 33c0 | xor eax, eax // e9???????? | // 833d????????00 | $sequence_12 = { 42 0fb6fa 8a1c07 881c06 8a5dff 881c07 8b5df8 } // n = 7, score = 300 // 42 | inc edx // 0fb6fa | movzx edi, dl // 8a1c07 | mov bl, byte ptr [edi + eax] // 881c06 | mov byte ptr [esi + eax], bl // 8a5dff | mov bl, byte ptr [ebp - 1] // 881c07 | mov byte ptr [edi + eax], bl // 8b5df8 | mov ebx, dword ptr [ebp - 8] $sequence_13 = { 0bd6 40 83f80e 72e7 } // n = 4, score = 300 // 0bd6 | or edx, esi // 40 | inc eax // 83f80e | cmp eax, 0xe // 72e7 | jb 0xffffffe9 $sequence_14 = { 83ec10 8365f800 837d0c00 8a8800010000 } // n = 4, score = 300 // 83ec10 | sub esp, 0x10 // 8365f800 | and dword ptr [ebp - 8], 0 // 837d0c00 | cmp dword ptr [ebp + 0xc], 0 // 8a8800010000 | mov cl, byte ptr [eax + 0x100] $sequence_15 = { ff75ec 1155f4 53 e8???????? 8bd8 } // n = 5, score = 300 // ff75ec | push dword ptr [ebp - 0x14] // 1155f4 | adc dword ptr [ebp - 0xc], edx // 53 | push ebx // e8???????? | // 8bd8 | mov ebx, eax condition: 7 of them and filesize < 204800 }