rule win_erbium_stealer_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.erbium_stealer."
        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.erbium_stealer"
        malpedia_rule_date = "20260422"
        malpedia_hash = "a182e35da64e6d71cb55f125c4d4225196523f14"
        malpedia_version = "20260504"
        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 = { 8b4508 50 ff55fc 6800800000 6a00 }
            // n = 5, score = 100
            //   8b4508               | mov                 eax, dword ptr [ebp + 8]
            //   50                   | push                eax
            //   ff55fc               | call                dword ptr [ebp - 4]
            //   6800800000           | push                0x8000
            //   6a00                 | push                0

        $sequence_1 = { 837de800 752b 6800800000 6a00 8b55f8 52 }
            // n = 6, score = 100
            //   837de800             | cmp                 dword ptr [ebp - 0x18], 0
            //   752b                 | jne                 0x2d
            //   6800800000           | push                0x8000
            //   6a00                 | push                0
            //   8b55f8               | mov                 edx, dword ptr [ebp - 8]
            //   52                   | push                edx

        $sequence_2 = { 51 8b5508 52 ff55fc 32c0 e9???????? 6a00 }
            // n = 7, score = 100
            //   51                   | push                ecx
            //   8b5508               | mov                 edx, dword ptr [ebp + 8]
            //   52                   | push                edx
            //   ff55fc               | call                dword ptr [ebp - 4]
            //   32c0                 | xor                 al, al
            //   e9????????           |                     
            //   6a00                 | push                0

        $sequence_3 = { 744a 51 51 51 }
            // n = 4, score = 100
            //   744a                 | je                  0x4c
            //   51                   | push                ecx
            //   51                   | push                ecx
            //   51                   | push                ecx

        $sequence_4 = { 8bd8 8944241c 8d8424a0000000 ba???????? }
            // n = 4, score = 100
            //   8bd8                 | mov                 ebx, eax
            //   8944241c             | mov                 dword ptr [esp + 0x1c], eax
            //   8d8424a0000000       | lea                 eax, [esp + 0xa0]
            //   ba????????           |                     

        $sequence_5 = { 8b5520 8955a4 8b4524 8945a8 6a00 }
            // n = 5, score = 100
            //   8b5520               | mov                 edx, dword ptr [ebp + 0x20]
            //   8955a4               | mov                 dword ptr [ebp - 0x5c], edx
            //   8b4524               | mov                 eax, dword ptr [ebp + 0x24]
            //   8945a8               | mov                 dword ptr [ebp - 0x58], eax
            //   6a00                 | push                0

        $sequence_6 = { 8b55ec 837a1000 7441 6a00 8b45ec }
            // n = 5, score = 100
            //   8b55ec               | mov                 edx, dword ptr [ebp - 0x14]
            //   837a1000             | cmp                 dword ptr [edx + 0x10], 0
            //   7441                 | je                  0x43
            //   6a00                 | push                0
            //   8b45ec               | mov                 eax, dword ptr [ebp - 0x14]

        $sequence_7 = { 034214 50 8b4dec 8b55f8 03510c 52 }
            // n = 6, score = 100
            //   034214               | add                 eax, dword ptr [edx + 0x14]
            //   50                   | push                eax
            //   8b4dec               | mov                 ecx, dword ptr [ebp - 0x14]
            //   8b55f8               | mov                 edx, dword ptr [ebp - 8]
            //   03510c               | add                 edx, dword ptr [ecx + 0xc]
            //   52                   | push                edx

        $sequence_8 = { 8b5110 52 8b45fc 50 ff55b0 }
            // n = 5, score = 100
            //   8b5110               | mov                 edx, dword ptr [ecx + 0x10]
            //   52                   | push                edx
            //   8b45fc               | mov                 eax, dword ptr [ebp - 4]
            //   50                   | push                eax
            //   ff55b0               | call                dword ptr [ebp - 0x50]

        $sequence_9 = { 8b4c2410 2bc7 3bc1 0f8284000000 }
            // n = 4, score = 100
            //   8b4c2410             | mov                 ecx, dword ptr [esp + 0x10]
            //   2bc7                 | sub                 eax, edi
            //   3bc1                 | cmp                 eax, ecx
            //   0f8284000000         | jb                  0x8a

    condition:
        7 of them and filesize < 33792
}