Actor(s): Leviathan
An uploader that can exfiltrate files to Dropbox.
rule win_lunchmoney_auto { meta: author = "Felix Bilstein - yara-signator at cocacoding dot com" date = "2023-07-11" version = "1" description = "Detects win.lunchmoney." 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.lunchmoney" malpedia_rule_date = "20230705" malpedia_hash = "42d0574f4405bd7d2b154d321d345acb18834a41" malpedia_version = "20230715" 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 = { 8bf1 894d80 c1e60a 56 e8???????? 56 8bf8 } // n = 7, score = 100 // 8bf1 | mov esi, ecx // 894d80 | mov dword ptr [ebp - 0x80], ecx // c1e60a | shl esi, 0xa // 56 | push esi // e8???????? | // 56 | push esi // 8bf8 | mov edi, eax $sequence_1 = { e8???????? c645fc03 8d4dd8 837dec10 8d5598 0f434dd8 e8???????? } // n = 7, score = 100 // e8???????? | // c645fc03 | mov byte ptr [ebp - 4], 3 // 8d4dd8 | lea ecx, [ebp - 0x28] // 837dec10 | cmp dword ptr [ebp - 0x14], 0x10 // 8d5598 | lea edx, [ebp - 0x68] // 0f434dd8 | cmovae ecx, dword ptr [ebp - 0x28] // e8???????? | $sequence_2 = { 51 50 ff7518 51 8d4d08 e8???????? } // n = 6, score = 100 // 51 | push ecx // 50 | push eax // ff7518 | push dword ptr [ebp + 0x18] // 51 | push ecx // 8d4d08 | lea ecx, [ebp + 8] // e8???????? | $sequence_3 = { 8bcf 83e71f c1f905 c1e706 8b0c8d50914200 c644390400 } // n = 6, score = 100 // 8bcf | mov ecx, edi // 83e71f | and edi, 0x1f // c1f905 | sar ecx, 5 // c1e706 | shl edi, 6 // 8b0c8d50914200 | mov ecx, dword ptr [ecx*4 + 0x429150] // c644390400 | mov byte ptr [ecx + edi + 4], 0 $sequence_4 = { 33db 895de8 c745fc02000000 8d4520 } // n = 4, score = 100 // 33db | xor ebx, ebx // 895de8 | mov dword ptr [ebp - 0x18], ebx // c745fc02000000 | mov dword ptr [ebp - 4], 2 // 8d4520 | lea eax, [ebp + 0x20] $sequence_5 = { 83e11f c1e106 8b048550914200 c644080401 } // n = 4, score = 100 // 83e11f | and ecx, 0x1f // c1e106 | shl ecx, 6 // 8b048550914200 | mov eax, dword ptr [eax*4 + 0x429150] // c644080401 | mov byte ptr [eax + ecx + 4], 1 $sequence_6 = { 8bcf 83e71f c1f905 c1e706 8b0c8d50914200 c644390400 85f6 } // n = 7, score = 100 // 8bcf | mov ecx, edi // 83e71f | and edi, 0x1f // c1f905 | sar ecx, 5 // c1e706 | shl edi, 6 // 8b0c8d50914200 | mov ecx, dword ptr [ecx*4 + 0x429150] // c644390400 | mov byte ptr [ecx + edi + 4], 0 // 85f6 | test esi, esi $sequence_7 = { 53 57 8d8ef8000000 e8???????? } // n = 4, score = 100 // 53 | push ebx // 57 | push edi // 8d8ef8000000 | lea ecx, [esi + 0xf8] // e8???????? | $sequence_8 = { 8d55ec e8???????? 8d55ec 8bc8 e8???????? 8d55ec 8bc8 } // n = 7, score = 100 // 8d55ec | lea edx, [ebp - 0x14] // e8???????? | // 8d55ec | lea edx, [ebp - 0x14] // 8bc8 | mov ecx, eax // e8???????? | // 8d55ec | lea edx, [ebp - 0x14] // 8bc8 | mov ecx, eax $sequence_9 = { 56 8bf1 57 8b5610 3bd3 0f82c6020000 8b7d10 } // n = 7, score = 100 // 56 | push esi // 8bf1 | mov esi, ecx // 57 | push edi // 8b5610 | mov edx, dword ptr [esi + 0x10] // 3bd3 | cmp edx, ebx // 0f82c6020000 | jb 0x2cc // 8b7d10 | mov edi, dword ptr [ebp + 0x10] condition: 7 of them and filesize < 373760 }
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