Actor(s): Comment Crew
There is no description at this point.
rule win_webc2_head_auto { meta: author = "Felix Bilstein - yara-signator at cocacoding dot com" date = "2023-12-06" version = "1" description = "Detects win.webc2_head." 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.webc2_head" malpedia_rule_date = "20231130" malpedia_hash = "fc8a0e9f343f6d6ded9e7df1a64dac0cc68d7351" malpedia_version = "20230808" 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 = { 8a8c0cc0000000 eb02 b13d c1e810 83e03f 0fbec9 } // n = 6, score = 100 // 8a8c0cc0000000 | mov cl, byte ptr [esp + ecx + 0xc0] // eb02 | jmp 4 // b13d | mov cl, 0x3d // c1e810 | shr eax, 0x10 // 83e03f | and eax, 0x3f // 0fbec9 | movsx ecx, cl $sequence_1 = { 68???????? 55 55 896c2434 ffd7 } // n = 5, score = 100 // 68???????? | // 55 | push ebp // 55 | push ebp // 896c2434 | mov dword ptr [esp + 0x34], ebp // ffd7 | call edi $sequence_2 = { 8d942444080000 03f0 51 50 52 55 ff15???????? } // n = 7, score = 100 // 8d942444080000 | lea edx, [esp + 0x844] // 03f0 | add esi, eax // 51 | push ecx // 50 | push eax // 52 | push edx // 55 | push ebp // ff15???????? | $sequence_3 = { e8???????? 83c40c 85c0 0f8554020000 b900050000 } // n = 5, score = 100 // e8???????? | // 83c40c | add esp, 0xc // 85c0 | test eax, eax // 0f8554020000 | jne 0x25a // b900050000 | mov ecx, 0x500 $sequence_4 = { 33db 89442418 52 c6450000 } // n = 4, score = 100 // 33db | xor ebx, ebx // 89442418 | mov dword ptr [esp + 0x18], eax // 52 | push edx // c6450000 | mov byte ptr [ebp], 0 $sequence_5 = { 7513 8dbc2444040000 83c9ff f2ae f7d1 49 894c241c } // n = 7, score = 100 // 7513 | jne 0x15 // 8dbc2444040000 | lea edi, [esp + 0x444] // 83c9ff | or ecx, 0xffffffff // f2ae | repne scasb al, byte ptr es:[edi] // f7d1 | not ecx // 49 | dec ecx // 894c241c | mov dword ptr [esp + 0x1c], ecx $sequence_6 = { 89442410 c1e002 89442418 8b4c2424 } // n = 4, score = 100 // 89442410 | mov dword ptr [esp + 0x10], eax // c1e002 | shl eax, 2 // 89442418 | mov dword ptr [esp + 0x18], eax // 8b4c2424 | mov ecx, dword ptr [esp + 0x24] $sequence_7 = { eb02 b03d 884303 8b442410 } // n = 4, score = 100 // eb02 | jmp 4 // b03d | mov al, 0x3d // 884303 | mov byte ptr [ebx + 3], al // 8b442410 | mov eax, dword ptr [esp + 0x10] $sequence_8 = { 83c410 c3 5f c6450000 5e } // n = 5, score = 100 // 83c410 | add esp, 0x10 // c3 | ret // 5f | pop edi // c6450000 | mov byte ptr [ebp], 0 // 5e | pop esi $sequence_9 = { 2500ff0000 45 3d003d0000 7435 } // n = 4, score = 100 // 2500ff0000 | and eax, 0xff00 // 45 | inc ebp // 3d003d0000 | cmp eax, 0x3d00 // 7435 | je 0x37 condition: 7 of them and filesize < 106496 }
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