{"group":"blackbasta","count":1,"rules":[{"rule_name":"blackbasta.yar","rule_text":"rule win_blackbasta_auto {\n\n    meta:\n        author = \"Felix Bilstein - yara-signator at cocacoding dot com\"\n        date = \"2023-07-11\"\n        version = \"1\"\n        description = \"Detects win.blackbasta.\"\n        info = \"autogenerated rule brought to you by yara-signator\"\n        tool = \"yara-signator v0.6.0\"\n        signator_config = \"callsandjumps;datarefs;binvalue\"\n        malpedia_reference = \"https://malpedia.caad.fkie.fraunhofer.de/details/win.blackbasta\"\n        malpedia_rule_date = \"20230705\"\n        malpedia_hash = \"42d0574f4405bd7d2b154d321d345acb18834a41\"\n        malpedia_version = \"20230715\"\n        malpedia_license = \"CC BY-SA 4.0\"\n        malpedia_sharing = \"TLP:WHITE\"\n\n    /* DISCLAIMER\n     * The strings used in this rule have been automatically selected from the\n     * disassembly of memory dumps and unpacked files, using YARA-Signator.\n     * The code and documentation is published here:\n     * https://github.com/fxb-cocacoding/yara-signator\n     * As Malpedia is used as data source, please note that for a given\n     * number of families, only single samples are documented.\n     * This likely impacts the degree of generalization these rules will offer.\n     * Take the described generation method also into consideration when you\n     * apply the rules in your use cases and assign them confidence levels.\n     */\n\n\n    strings:\n        $sequence_0 = { b8ffffff7f 8bd1 d1ea 2bc2 57 3bc8 7607 }\n            // n = 7, score = 100\n            //   b8ffffff7f           | mov                 eax, 0x7fffffff\n            //   8bd1                 | mov                 edx, ecx\n            //   d1ea                 | shr                 edx, 1\n            //   2bc2                 | sub                 eax, edx\n            //   57                   | push                edi\n            //   3bc8                 | cmp                 ecx, eax\n            //   7607                 | jbe                 9\n\n        $sequence_1 = { 6800000080 ff15???????? 85c0 754d 837d1c08 8d4d08 }\n            // n = 6, score = 100\n            //   6800000080           | push                0x80000000\n            //   ff15????????         |                     \n            //   85c0                 | test                eax, eax\n            //   754d                 | jne                 0x4f\n            //   837d1c08             | cmp                 dword ptr [ebp + 0x1c], 8\n            //   8d4d08               | lea                 ecx, [ebp + 8]\n\n        $sequence_2 = { c745bc0f000000 884da8 8b03 c745fc04000000 8b702c 8d8560ffffff }\n            // n = 6, score = 100\n            //   c745bc0f000000       | mov                 dword ptr [ebp - 0x44], 0xf\n            //   884da8               | mov                 byte ptr [ebp - 0x58], cl\n            //   8b03                 | mov                 eax, dword ptr [ebx]\n            //   c745fc04000000       | mov                 dword ptr [ebp - 4], 4\n            //   8b702c               | mov                 esi, dword ptr [eax + 0x2c]\n            //   8d8560ffffff         | lea                 eax, [ebp - 0xa0]\n\n        $sequence_3 = { 8bec 83ec14 56 8b7508 ff34b5bc430a10 e8???????? 50 }\n            // n = 7, score = 100\n            //   8bec                 | mov                 ebp, esp\n            //   83ec14               | sub                 esp, 0x14\n            //   56                   | push                esi\n            //   8b7508               | mov                 esi, dword ptr [ebp + 8]\n            //   ff34b5bc430a10       | push                dword ptr [esi*4 + 0x100a43bc]\n            //   e8????????           |                     \n            //   50                   | push                eax\n\n        $sequence_4 = { 83453040 41 8345340c 8b7d4c 8b5550 894d0c 85ff }\n            // n = 7, score = 100\n            //   83453040             | add                 dword ptr [ebp + 0x30], 0x40\n            //   41                   | inc                 ecx\n            //   8345340c             | add                 dword ptr [ebp + 0x34], 0xc\n            //   8b7d4c               | mov                 edi, dword ptr [ebp + 0x4c]\n            //   8b5550               | mov                 edx, dword ptr [ebp + 0x50]\n            //   894d0c               | mov                 dword ptr [ebp + 0xc], ecx\n            //   85ff                 | test                edi, edi\n\n        $sequence_5 = { 8945ec 57 ff7508 ff7704 ff37 e8???????? 83c410 }\n            // n = 7, score = 100\n            //   8945ec               | mov                 dword ptr [ebp - 0x14], eax\n            //   57                   | push                edi\n            //   ff7508               | push                dword ptr [ebp + 8]\n            //   ff7704               | push                dword ptr [edi + 4]\n            //   ff37                 | push                dword ptr [edi]\n            //   e8????????           |                     \n            //   83c410               | add                 esp, 0x10\n\n        $sequence_6 = { 0540420f00 8945ec 83d100 894de8 eb14 c745ecffffffff }\n            // n = 6, score = 100\n            //   0540420f00           | add                 eax, 0xf4240\n            //   8945ec               | mov                 dword ptr [ebp - 0x14], eax\n            //   83d100               | adc                 ecx, 0\n            //   894de8               | mov                 dword ptr [ebp - 0x18], ecx\n            //   eb14                 | jmp                 0x16\n            //   c745ecffffffff       | mov                 dword ptr [ebp - 0x14], 0xffffffff\n\n        $sequence_7 = { 64a100000000 50 64892500000000 83ec34 56 57 8d45c0 }\n            // n = 7, score = 100\n            //   64a100000000         | mov                 eax, dword ptr fs:[0]\n            //   50                   | push                eax\n            //   64892500000000       | mov                 dword ptr fs:[0], esp\n            //   83ec34               | sub                 esp, 0x34\n            //   56                   | push                esi\n            //   57                   | push                edi\n            //   8d45c0               | lea                 eax, [ebp - 0x40]\n\n        $sequence_8 = { 6a00 53 51 8bcf ff501c 5f 5e }\n            // n = 7, score = 100\n            //   6a00                 | push                0\n            //   53                   | push                ebx\n            //   51                   | push                ecx\n            //   8bcf                 | mov                 ecx, edi\n            //   ff501c               | call                dword ptr [eax + 0x1c]\n            //   5f                   | pop                 edi\n            //   5e                   | pop                 esi\n\n        $sequence_9 = { c645b400 3b35???????? 740f ff7620 e8???????? 83c404 8bd0 }\n            // n = 7, score = 100\n            //   c645b400             | mov                 byte ptr [ebp - 0x4c], 0\n            //   3b35????????         |                     \n            //   740f                 | je                  0x11\n            //   ff7620               | push                dword ptr [esi + 0x20]\n            //   e8????????           |                     \n            //   83c404               | add                 esp, 4\n            //   8bd0                 | mov                 edx, eax\n\n    condition:\n        7 of them and filesize < 1758208\n}","sha256":"9138a5302d8b19f4a2086f2ca6c947482f32cd7add668782e1b544eb9e591ca9","byte_size":7464,"updated_at":"2026-06-24 05:15:59"}]}