Actor(s): Thrip
There is no description at this point.
rule win_catchamas_auto { meta: author = "Felix Bilstein - yara-signator at cocacoding dot com" date = "2026-01-05" version = "1" description = "Detects win.catchamas." 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.catchamas" 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 = { 84c9 75f1 833d????????ff 740c 8db42470100000 } // n = 5, score = 200 // 84c9 | test cl, cl // 75f1 | jne 0xfffffff3 // 833d????????ff | // 740c | je 0xe // 8db42470100000 | lea esi, [esp + 0x1070] $sequence_1 = { 40 e8???????? 85db 7411 } // n = 4, score = 200 // 40 | inc eax // e8???????? | // 85db | test ebx, ebx // 7411 | je 0x13 $sequence_2 = { 8bf1 897c2418 c644241c00 e8???????? 68???????? } // n = 5, score = 200 // 8bf1 | mov esi, ecx // 897c2418 | mov dword ptr [esp + 0x18], edi // c644241c00 | mov byte ptr [esp + 0x1c], 0 // e8???????? | // 68???????? | $sequence_3 = { 83d200 8955d0 7554 83f8ff } // n = 4, score = 200 // 83d200 | adc edx, 0 // 8955d0 | mov dword ptr [ebp - 0x30], edx // 7554 | jne 0x56 // 83f8ff | cmp eax, -1 $sequence_4 = { 6a14 81e300800000 ffd7 83e001 33c9 8bff baba000000 } // n = 7, score = 200 // 6a14 | push 0x14 // 81e300800000 | and ebx, 0x8000 // ffd7 | call edi // 83e001 | and eax, 1 // 33c9 | xor ecx, ecx // 8bff | mov edi, edi // baba000000 | mov edx, 0xba $sequence_5 = { ff15???????? 56 8be8 55 53 } // n = 5, score = 200 // ff15???????? | // 56 | push esi // 8be8 | mov ebp, eax // 55 | push ebp // 53 | push ebx $sequence_6 = { 6a00 52 c745dc00000000 e8???????? 8b45dc 6a00 8d4de8 } // n = 7, score = 200 // 6a00 | push 0 // 52 | push edx // c745dc00000000 | mov dword ptr [ebp - 0x24], 0 // e8???????? | // 8b45dc | mov eax, dword ptr [ebp - 0x24] // 6a00 | push 0 // 8d4de8 | lea ecx, [ebp - 0x18] $sequence_7 = { 8b45e0 7409 e8???????? 8bfc eb32 83c9ff } // n = 6, score = 200 // 8b45e0 | mov eax, dword ptr [ebp - 0x20] // 7409 | je 0xb // e8???????? | // 8bfc | mov edi, esp // eb32 | jmp 0x34 // 83c9ff | or ecx, 0xffffffff $sequence_8 = { 66894e14 5e 8b8c2404080000 33cc e8???????? } // n = 5, score = 200 // 66894e14 | mov word ptr [esi + 0x14], cx // 5e | pop esi // 8b8c2404080000 | mov ecx, dword ptr [esp + 0x804] // 33cc | xor ecx, esp // e8???????? | $sequence_9 = { e8???????? 682000cc00 53 53 56 57 55 } // n = 7, score = 200 // e8???????? | // 682000cc00 | push 0xcc0020 // 53 | push ebx // 53 | push ebx // 56 | push esi // 57 | push edi // 55 | push ebp condition: 7 of them and filesize < 368640 }
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