Actor(s): APT5
There is no description at this point.
rule win_leouncia_auto { meta: author = "Felix Bilstein - yara-signator at cocacoding dot com" date = "2026-01-05" version = "1" description = "Detects win.leouncia." 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.leouncia" malpedia_rule_date = "20260105" malpedia_hash = "19b79e7cab4eaf532122e5b45a77dd8f6bb5cc79" malpedia_version = "20251219" 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 = { 50 c644141800 ff15???????? 85c0 7512 ff15???????? 83f805 } // n = 7, score = 100 // 50 | push eax // c644141800 | mov byte ptr [esp + edx + 0x18], 0 // ff15???????? | // 85c0 | test eax, eax // 7512 | jne 0x14 // ff15???????? | // 83f805 | cmp eax, 5 $sequence_1 = { 3bf3 7519 8b35???????? 55 } // n = 4, score = 100 // 3bf3 | cmp esi, ebx // 7519 | jne 0x1b // 8b35???????? | // 55 | push ebp $sequence_2 = { 895c2464 ff15???????? 85c0 7520 } // n = 4, score = 100 // 895c2464 | mov dword ptr [esp + 0x64], ebx // ff15???????? | // 85c0 | test eax, eax // 7520 | jne 0x22 $sequence_3 = { 8dbc247c040000 2bd6 8bca 89542418 8be9 c1e902 f3a5 } // n = 7, score = 100 // 8dbc247c040000 | lea edi, [esp + 0x47c] // 2bd6 | sub edx, esi // 8bca | mov ecx, edx // 89542418 | mov dword ptr [esp + 0x18], edx // 8be9 | mov ebp, ecx // c1e902 | shr ecx, 2 // f3a5 | rep movsd dword ptr es:[edi], dword ptr [esi] $sequence_4 = { 7505 c6440c2820 41 3bc8 7cee 8b842434050000 56 } // n = 7, score = 100 // 7505 | jne 7 // c6440c2820 | mov byte ptr [esp + ecx + 0x28], 0x20 // 41 | inc ecx // 3bc8 | cmp ecx, eax // 7cee | jl 0xfffffff0 // 8b842434050000 | mov eax, dword ptr [esp + 0x534] // 56 | push esi $sequence_5 = { 50 e8???????? 8d4c2424 51 e8???????? 8b2d???????? 83c410 } // n = 7, score = 100 // 50 | push eax // e8???????? | // 8d4c2424 | lea ecx, [esp + 0x24] // 51 | push ecx // e8???????? | // 8b2d???????? | // 83c410 | add esp, 0x10 $sequence_6 = { e8???????? 8b4c2420 83c40c 889c0c14010000 } // n = 4, score = 100 // e8???????? | // 8b4c2420 | mov ecx, dword ptr [esp + 0x20] // 83c40c | add esp, 0xc // 889c0c14010000 | mov byte ptr [esp + ecx + 0x114], bl $sequence_7 = { 8d542440 8d442450 8d8c24b4040000 52 } // n = 4, score = 100 // 8d542440 | lea edx, [esp + 0x40] // 8d442450 | lea eax, [esp + 0x50] // 8d8c24b4040000 | lea ecx, [esp + 0x4b4] // 52 | push edx $sequence_8 = { 8b0f 52 50 51 6a00 ff15???????? } // n = 6, score = 100 // 8b0f | mov ecx, dword ptr [edi] // 52 | push edx // 50 | push eax // 51 | push ecx // 6a00 | push 0 // ff15???????? | $sequence_9 = { 89942444040000 8b542434 8bc1 8bf5 } // n = 4, score = 100 // 89942444040000 | mov dword ptr [esp + 0x444], edx // 8b542434 | mov edx, dword ptr [esp + 0x34] // 8bc1 | mov eax, ecx // 8bf5 | mov esi, ebp condition: 7 of them and filesize < 114688 }
If your designated proposal does not fit in any other category, feel free to write a free-text in the comment field below. Changes regarding references should be proposed on the Malpedia library page.
Your suggestion will be reviewed before being published. Thank you for contributing!
YYYY-MM-DD
YYYY-MM
YYYY