Actor(s): Equation Group
FancyFilter is a piece of code that documents code overlap between frameworks used by Regin and Equation Group.
rule win_fancyfilter_auto { meta: author = "Felix Bilstein - yara-signator at cocacoding dot com" date = "2023-07-11" version = "1" description = "Detects win.fancyfilter." 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.fancyfilter" 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 = { 8b07 83e810 50 83c610 } // n = 4, score = 400 // 8b07 | mov eax, dword ptr [edi] // 83e810 | sub eax, 0x10 // 50 | push eax // 83c610 | add esi, 0x10 $sequence_1 = { ff15???????? 85c0 750d 8b472c a801 } // n = 5, score = 400 // ff15???????? | // 85c0 | test eax, eax // 750d | jne 0xf // 8b472c | mov eax, dword ptr [edi + 0x2c] // a801 | test al, 1 $sequence_2 = { 83c012 50 ffd6 a1???????? } // n = 4, score = 400 // 83c012 | add eax, 0x12 // 50 | push eax // ffd6 | call esi // a1???????? | $sequence_3 = { 740f 8d4f20 51 50 ff15???????? } // n = 5, score = 400 // 740f | je 0x11 // 8d4f20 | lea ecx, [edi + 0x20] // 51 | push ecx // 50 | push eax // ff15???????? | $sequence_4 = { 740f 8d4f20 51 50 ff15???????? 8b36 } // n = 6, score = 400 // 740f | je 0x11 // 8d4f20 | lea ecx, [edi + 0x20] // 51 | push ecx // 50 | push eax // ff15???????? | // 8b36 | mov esi, dword ptr [esi] $sequence_5 = { 7502 b001 5e 5f } // n = 4, score = 400 // 7502 | jne 4 // b001 | mov al, 1 // 5e | pop esi // 5f | pop edi $sequence_6 = { 740a 66833800 7404 b001 eb02 32c0 } // n = 6, score = 400 // 740a | je 0xc // 66833800 | cmp word ptr [eax], 0 // 7404 | je 6 // b001 | mov al, 1 // eb02 | jmp 4 // 32c0 | xor al, al $sequence_7 = { 7502 b001 5e 5f 5b } // n = 5, score = 400 // 7502 | jne 4 // b001 | mov al, 1 // 5e | pop esi // 5f | pop edi // 5b | pop ebx $sequence_8 = { 85c0 740a 66833800 7404 b001 } // n = 5, score = 400 // 85c0 | test eax, eax // 740a | je 0xc // 66833800 | cmp word ptr [eax], 0 // 7404 | je 6 // b001 | mov al, 1 $sequence_9 = { 83c030 eb03 83c057 8801 49 } // n = 5, score = 400 // 83c030 | add eax, 0x30 // eb03 | jmp 5 // 83c057 | add eax, 0x57 // 8801 | mov byte ptr [ecx], al // 49 | dec ecx condition: 7 of them and filesize < 169984 }
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