rule win_kamasers_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.kamasers."
        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.kamasers"
        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 = { e8???????? 8b4db8 46 41 eb75 6a0c 8bcf }
            // n = 7, score = 100
            //   e8????????           |                     
            //   8b4db8               | mov                 ecx, dword ptr [ebp - 0x48]
            //   46                   | inc                 esi
            //   41                   | inc                 ecx
            //   eb75                 | jmp                 0x77
            //   6a0c                 | push                0xc
            //   8bcf                 | mov                 ecx, edi

        $sequence_1 = { 8b07 8bcf ff5008 837df00f 8d4604 0f57c0 }
            // n = 6, score = 100
            //   8b07                 | mov                 eax, dword ptr [edi]
            //   8bcf                 | mov                 ecx, edi
            //   ff5008               | call                dword ptr [eax + 8]
            //   837df00f             | cmp                 dword ptr [ebp - 0x10], 0xf
            //   8d4604               | lea                 eax, [esi + 4]
            //   0f57c0               | xorps               xmm0, xmm0

        $sequence_2 = { 52 e8???????? 83c408 8b856cffffff c78510feffff00000000 c78514feffff0f000000 c68500feffff00 }
            // n = 7, score = 100
            //   52                   | push                edx
            //   e8????????           |                     
            //   83c408               | add                 esp, 8
            //   8b856cffffff         | mov                 eax, dword ptr [ebp - 0x94]
            //   c78510feffff00000000     | mov    dword ptr [ebp - 0x1f0], 0
            //   c78514feffff0f000000     | mov    dword ptr [ebp - 0x1ec], 0xf
            //   c68500feffff00       | mov                 byte ptr [ebp - 0x200], 0

        $sequence_3 = { 8bf9 ba11000000 8bc7 2bf7 0f1107 c6471000 0f1f00 }
            // n = 7, score = 100
            //   8bf9                 | mov                 edi, ecx
            //   ba11000000           | mov                 edx, 0x11
            //   8bc7                 | mov                 eax, edi
            //   2bf7                 | sub                 esi, edi
            //   0f1107               | movups              xmmword ptr [edi], xmm0
            //   c6471000             | mov                 byte ptr [edi + 0x10], 0
            //   0f1f00               | nop                 dword ptr [eax]

        $sequence_4 = { c78508feffff03000000 c60053 398d0cfeffff 0f4785f8fdffff c6400165 8d85f8fdffff 398d0cfeffff }
            // n = 7, score = 100
            //   c78508feffff03000000     | mov    dword ptr [ebp - 0x1f8], 3
            //   c60053               | mov                 byte ptr [eax], 0x53
            //   398d0cfeffff         | cmp                 dword ptr [ebp - 0x1f4], ecx
            //   0f4785f8fdffff       | cmova               eax, dword ptr [ebp - 0x208]
            //   c6400165             | mov                 byte ptr [eax + 1], 0x65
            //   8d85f8fdffff         | lea                 eax, [ebp - 0x208]
            //   398d0cfeffff         | cmp                 dword ptr [ebp - 0x1f4], ecx

        $sequence_5 = { 66f3ab 8b7df0 8b4d10 2bf9 8d047d02000000 8b7df8 50 }
            // n = 7, score = 100
            //   66f3ab               | rep stosd           dword ptr es:[edi], eax
            //   8b7df0               | mov                 edi, dword ptr [ebp - 0x10]
            //   8b4d10               | mov                 ecx, dword ptr [ebp + 0x10]
            //   2bf9                 | sub                 edi, ecx
            //   8d047d02000000       | lea                 eax, [edi*2 + 2]
            //   8b7df8               | mov                 edi, dword ptr [ebp - 8]
            //   50                   | push                eax

        $sequence_6 = { 8bd9 895dec 8b450c 8bc8 8b7508 2bce 8945f0 }
            // n = 7, score = 100
            //   8bd9                 | mov                 ebx, ecx
            //   895dec               | mov                 dword ptr [ebp - 0x14], ebx
            //   8b450c               | mov                 eax, dword ptr [ebp + 0xc]
            //   8bc8                 | mov                 ecx, eax
            //   8b7508               | mov                 esi, dword ptr [ebp + 8]
            //   2bce                 | sub                 ecx, esi
            //   8945f0               | mov                 dword ptr [ebp - 0x10], eax

        $sequence_7 = { 8b0d???????? 49 890d???????? 89048d947df904 5d c3 55 }
            // n = 7, score = 100
            //   8b0d????????         |                     
            //   49                   | dec                 ecx
            //   890d????????         |                     
            //   89048d947df904       | mov                 dword ptr [ecx*4 + 0x4f97d94], eax
            //   5d                   | pop                 ebp
            //   c3                   | ret                 
            //   55                   | push                ebp

        $sequence_8 = { 83c404 ba???????? 8bc8 e8???????? c645fc1c 8b8dc8fdffff }
            // n = 6, score = 100
            //   83c404               | add                 esp, 4
            //   ba????????           |                     
            //   8bc8                 | mov                 ecx, eax
            //   e8????????           |                     
            //   c645fc1c             | mov                 byte ptr [ebp - 4], 0x1c
            //   8b8dc8fdffff         | mov                 ecx, dword ptr [ebp - 0x238]

        $sequence_9 = { 0f87ef010000 ff2485e19df604 8b7e08 33c0 884638 384714 7507 }
            // n = 7, score = 100
            //   0f87ef010000         | ja                  0x1f5
            //   ff2485e19df604       | jmp                 dword ptr [eax*4 + 0x4f69de1]
            //   8b7e08               | mov                 edi, dword ptr [esi + 8]
            //   33c0                 | xor                 eax, eax
            //   884638               | mov                 byte ptr [esi + 0x38], al
            //   384714               | cmp                 byte ptr [edi + 0x14], al
            //   7507                 | jne                 9

    condition:
        7 of them and filesize < 906240
}