Actor(s): APT32
There is no description at this point.
rule win_kerrdown_auto { meta: author = "Felix Bilstein - yara-signator at cocacoding dot com" date = "2023-12-06" version = "1" description = "Detects win.kerrdown." 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.kerrdown" 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 = { 5d c20800 85f6 75b2 83ff10 8935???????? b8???????? } // n = 7, score = 200 // 5d | pop ebp // c20800 | ret 8 // 85f6 | test esi, esi // 75b2 | jne 0xffffffb4 // 83ff10 | cmp edi, 0x10 // 8935???????? | // b8???????? | $sequence_1 = { 8bec 8b0d???????? b8???????? 8b15???????? 57 8b3d???????? 83ff10 } // n = 7, score = 200 // 8bec | mov ebp, esp // 8b0d???????? | // b8???????? | // 8b15???????? | // 57 | push edi // 8b3d???????? | // 83ff10 | cmp edi, 0x10 $sequence_2 = { 8aca c0e206 c0e902 80e10f 02c8 8a45eb 243f } // n = 7, score = 200 // 8aca | mov cl, dl // c0e206 | shl dl, 6 // c0e902 | shr cl, 2 // 80e10f | and cl, 0xf // 02c8 | add cl, al // 8a45eb | mov al, byte ptr [ebp - 0x15] // 243f | and al, 0x3f $sequence_3 = { b8???????? 0f43d1 b9???????? 2bc2 50 } // n = 5, score = 200 // b8???????? | // 0f43d1 | cmovae edx, ecx // b9???????? | // 2bc2 | sub eax, edx // 50 | push eax $sequence_4 = { 0f43c1 3d???????? 773e 83ff10 } // n = 4, score = 200 // 0f43c1 | cmovae eax, ecx // 3d???????? | // 773e | ja 0x40 // 83ff10 | cmp edi, 0x10 $sequence_5 = { 83ff10 ba???????? b8???????? 0f43d1 b9???????? 2bc2 } // n = 6, score = 200 // 83ff10 | cmp edi, 0x10 // ba???????? | // b8???????? | // 0f43d1 | cmovae edx, ecx // b9???????? | // 2bc2 | sub eax, edx $sequence_6 = { 80e10f 02c8 8a45eb 243f } // n = 4, score = 200 // 80e10f | and cl, 0xf // 02c8 | add cl, al // 8a45eb | mov al, byte ptr [ebp - 0x15] // 243f | and al, 0x3f $sequence_7 = { ff750c 83ff10 ba???????? b8???????? 0f43d1 b9???????? 2bc2 } // n = 7, score = 200 // ff750c | push dword ptr [ebp + 0xc] // 83ff10 | cmp edi, 0x10 // ba???????? | // b8???????? | // 0f43d1 | cmovae edx, ecx // b9???????? | // 2bc2 | sub eax, edx $sequence_8 = { e8???????? 46 83fe03 7cec 8b4de0 } // n = 5, score = 200 // e8???????? | // 46 | inc esi // 83fe03 | cmp esi, 3 // 7cec | jl 0xffffffee // 8b4de0 | mov ecx, dword ptr [ebp - 0x20] $sequence_9 = { 0f854d0d0000 eb00 f30f7e442404 660f2815???????? 660f28c8 } // n = 5, score = 200 // 0f854d0d0000 | jne 0xd53 // eb00 | jmp 2 // f30f7e442404 | movq xmm0, qword ptr [esp + 4] // 660f2815???????? | // 660f28c8 | movapd xmm1, xmm0 condition: 7 of them and filesize < 278528 }
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