According to Cyble, this is a stealer targeting several crypto currency wallets along browser data.
rule win_temp_stealer_auto { meta: author = "Felix Bilstein - yara-signator at cocacoding dot com" date = "2026-09-17" version = "1" description = "Detects win.temp_stealer." 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.temp_stealer" 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 = { 488b09 ff15???????? 488bd8 488d1539b00300 488bc8 ff15???????? 488985f8040000 } // n = 7, score = 100 // 488b09 | mov dword ptr [esp + 0x68], eax // ff15???????? | // 488bd8 | dec eax // 488d1539b00300 | mov dword ptr [ebp - 0x69], eax // 488bc8 | dec eax // ff15???????? | // 488985f8040000 | mov dword ptr [ebp - 0x59], eax $sequence_1 = { e8???????? 488b0f 4885c9 7426 488d59f8 4d8bcd 4c8b03 } // n = 7, score = 100 // e8???????? | // 488b0f | lea ecx, [ebp - 0x60] // 4885c9 | nop // 7426 | mov edi, 0x10000 // 488d59f8 | dec eax // 4d8bcd | cmp esi, edi // 4c8b03 | cmovl edi, esi $sequence_2 = { 4055 4883ec20 488bea b810000000 48f7a580000000 488bd0 48c7c0ffffffff } // n = 7, score = 100 // 4055 | test eax, eax // 4883ec20 | je 0xe83 // 488bea | jne 0xfad // b810000000 | dec eax // 48f7a580000000 | mov dword ptr [esp + 0x20], ebx // 488bd0 | dec esp // 48c7c0ffffffff | lea ecx, [ebp + 0x4e0] $sequence_3 = { e8???????? 90 488b03 833800 7513 488d15e1b30100 488d0dbab30100 } // n = 7, score = 100 // e8???????? | // 90 | lea edx, [ebp - 0x20] // 488b03 | dec eax // 833800 | lea ecx, [ebp + 0xd8] // 7513 | dec eax // 488d15e1b30100 | mov edx, eax // 488d0dbab30100 | dec eax $sequence_4 = { 488d55d0 488bcb e8???????? 90 4c8d058e300300 488d55c0 488bc8 } // n = 7, score = 100 // 488d55d0 | dec eax // 488bcb | mov ebx, dword ptr [esp + 0x340] // e8???????? | // 90 | dec eax // 4c8d058e300300 | lea ecx, [ebp - 0x20] // 488d55c0 | nop // 488bc8 | dec eax $sequence_5 = { e8???????? 488b8d50050000 ff9568050000 488b8d60050000 ff5508 488d4c2448 48837c246008 } // n = 7, score = 100 // e8???????? | // 488b8d50050000 | dec eax // ff9568050000 | mov ebx, ecx // 488b8d60050000 | dec eax // ff5508 | mov eax, dword ptr [ecx] // 488d4c2448 | dec eax // 48837c246008 | arpl word ptr [eax + 4], cx $sequence_6 = { c644242c00 488d542420 488bcb e8???????? 4c89642438 458d6508 4c89642430 } // n = 7, score = 100 // c644242c00 | push edi // 488d542420 | dec eax // 488bcb | sub esp, 0x20 // e8???????? | // 4c89642438 | nop // 458d6508 | jmp 0x91 // 4c89642430 | dec eax $sequence_7 = { 894708 488d5901 41bf20000000 418bc7 48f7e3 498d4fdf 480f40c1 } // n = 7, score = 100 // 894708 | mov eax, dword ptr [esi] // 488d5901 | dec eax // 41bf20000000 | arpl word ptr [eax + 4], cx // 418bc7 | dec eax // 48f7e3 | add ecx, esi // 498d4fdf | inc ebp // 480f40c1 | xor eax, eax $sequence_8 = { f30f7f442478 6644896c2468 488d9500030000 488d4c2468 e8???????? 90 4c8bc3 } // n = 7, score = 100 // f30f7f442478 | lea ecx, [edx + 0x158] // 6644896c2468 | dec eax // 488d9500030000 | mov ecx, dword ptr [edx + 0x348] // 488d4c2468 | dec eax // e8???????? | // 90 | lea ecx, [edx + 0xe0] // 4c8bc3 | dec eax $sequence_9 = { 488903 408828 c7430801000000 488b5c2430 488b6c2438 488b742440 4883c420 } // n = 7, score = 100 // 488903 | dec eax // 408828 | mov dword ptr [ecx], eax // c7430801000000 | mov ebx, edx // 488b5c2430 | dec eax // 488b6c2438 | add ecx, 8 // 488b742440 | dec eax // 4883c420 | sub esp, 0x20 condition: 7 of them and filesize < 652288 }
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