Actor(s): Sofacy
There is no description at this point.
rule win_downdelph_auto { meta: author = "Felix Bilstein - yara-signator at cocacoding dot com" date = "2023-01-25" version = "1" description = "Detects win.downdelph." 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.downdelph" malpedia_rule_date = "20230124" malpedia_hash = "2ee0eebba83dce3d019a90519f2f972c0fcf9686" malpedia_version = "20230125" 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 = { 83c604 4d 75ee eb7c } // n = 4, score = 100 // 83c604 | add esi, 4 // 4d | dec ebp // 75ee | jne 0xfffffff0 // eb7c | jmp 0x7e $sequence_1 = { 83c404 8b07 8b55fc b900000000 e8???????? } // n = 5, score = 100 // 83c404 | add esp, 4 // 8b07 | mov eax, dword ptr [edi] // 8b55fc | mov edx, dword ptr [ebp - 4] // b900000000 | mov ecx, 0 // e8???????? | $sequence_2 = { 8b45f8 e8???????? 50 68???????? 8b45ec 50 } // n = 6, score = 100 // 8b45f8 | mov eax, dword ptr [ebp - 8] // e8???????? | // 50 | push eax // 68???????? | // 8b45ec | mov eax, dword ptr [ebp - 0x14] // 50 | push eax $sequence_3 = { a1???????? 8b14b8 8d45e0 b9???????? e8???????? } // n = 5, score = 100 // a1???????? | // 8b14b8 | mov edx, dword ptr [eax + edi*4] // 8d45e0 | lea eax, [ebp - 0x20] // b9???????? | // e8???????? | $sequence_4 = { b900040000 6a00 e8???????? 8b95e0fbffff 8bc3 e8???????? } // n = 6, score = 100 // b900040000 | mov ecx, 0x400 // 6a00 | push 0 // e8???????? | // 8b95e0fbffff | mov edx, dword ptr [ebp - 0x420] // 8bc3 | mov eax, ebx // e8???????? | $sequence_5 = { e8???????? 754e 8b55f0 8b45f4 e8???????? } // n = 5, score = 100 // e8???????? | // 754e | jne 0x50 // 8b55f0 | mov edx, dword ptr [ebp - 0x10] // 8b45f4 | mov eax, dword ptr [ebp - 0xc] // e8???????? | $sequence_6 = { 6a00 6800000080 6a00 6a00 8b45fc e8???????? 50 } // n = 7, score = 100 // 6a00 | push 0 // 6800000080 | push 0x80000000 // 6a00 | push 0 // 6a00 | push 0 // 8b45fc | mov eax, dword ptr [ebp - 4] // e8???????? | // 50 | push eax $sequence_7 = { 85c0 7464 8b45fc 8b3c98 85ff 7405 83ef04 } // n = 7, score = 100 // 85c0 | test eax, eax // 7464 | je 0x66 // 8b45fc | mov eax, dword ptr [ebp - 4] // 8b3c98 | mov edi, dword ptr [eax + ebx*4] // 85ff | test edi, edi // 7405 | je 7 // 83ef04 | sub edi, 4 $sequence_8 = { 8bca 0fb6f8 d3ef 8bcf 80e101 } // n = 5, score = 100 // 8bca | mov ecx, edx // 0fb6f8 | movzx edi, al // d3ef | shr edi, cl // 8bcf | mov ecx, edi // 80e101 | and cl, 1 $sequence_9 = { 8d45d8 8b55fc 8b14ba e8???????? 8b55d8 b901000000 b8???????? } // n = 7, score = 100 // 8d45d8 | lea eax, [ebp - 0x28] // 8b55fc | mov edx, dword ptr [ebp - 4] // 8b14ba | mov edx, dword ptr [edx + edi*4] // e8???????? | // 8b55d8 | mov edx, dword ptr [ebp - 0x28] // b901000000 | mov ecx, 1 // b8???????? | condition: 7 of them and filesize < 172032 }
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