rule win_dispenserxfs_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.dispenserxfs."
        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.dispenserxfs"
        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 = { ff30 8d45c4 53 68???????? 6a1f 50 }
            // n = 6, score = 200
            //   ff30                 | push                dword ptr [eax]
            //   8d45c4               | lea                 eax, [ebp - 0x3c]
            //   53                   | push                ebx
            //   68????????           |                     
            //   6a1f                 | push                0x1f
            //   50                   | push                eax

        $sequence_1 = { 68ff0f0000 53 50 8bf1 889df8eeffff e8???????? 83c40c }
            // n = 7, score = 200
            //   68ff0f0000           | push                0xfff
            //   53                   | push                ebx
            //   50                   | push                eax
            //   8bf1                 | mov                 esi, ecx
            //   889df8eeffff         | mov                 byte ptr [ebp - 0x1108], bl
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc

        $sequence_2 = { 59 59 68e8030000 ff15???????? 4e }
            // n = 5, score = 200
            //   59                   | pop                 ecx
            //   59                   | pop                 ecx
            //   68e8030000           | push                0x3e8
            //   ff15????????         |                     
            //   4e                   | dec                 esi

        $sequence_3 = { c785d0feffff55534420 c785d4feffff41555344 899dd8feffff 898ddcfeffff 898de0feffff 89b5e4feffff 89b5e8feffff }
            // n = 7, score = 200
            //   c785d0feffff55534420     | mov    dword ptr [ebp - 0x130], 0x20445355
            //   c785d4feffff41555344     | mov    dword ptr [ebp - 0x12c], 0x44535541
            //   899dd8feffff         | mov                 dword ptr [ebp - 0x128], ebx
            //   898ddcfeffff         | mov                 dword ptr [ebp - 0x124], ecx
            //   898de0feffff         | mov                 dword ptr [ebp - 0x120], ecx
            //   89b5e4feffff         | mov                 dword ptr [ebp - 0x11c], esi
            //   89b5e8feffff         | mov                 dword ptr [ebp - 0x118], esi

        $sequence_4 = { 8bf9 8845da 8d4dd8 668b4508 }
            // n = 4, score = 200
            //   8bf9                 | mov                 edi, ecx
            //   8845da               | mov                 byte ptr [ebp - 0x26], al
            //   8d4dd8               | lea                 ecx, [ebp - 0x28]
            //   668b4508             | mov                 ax, word ptr [ebp + 8]

        $sequence_5 = { 89b5c1fdffff c785c5fdffff48474000 c785c9fdffff55534420 c685cdfdffff42 }
            // n = 4, score = 200
            //   89b5c1fdffff         | mov                 dword ptr [ebp - 0x23f], esi
            //   c785c5fdffff48474000     | mov    dword ptr [ebp - 0x23b], 0x404748
            //   c785c9fdffff55534420     | mov    dword ptr [ebp - 0x237], 0x20445355
            //   c685cdfdffff42       | mov                 byte ptr [ebp - 0x233], 0x42

        $sequence_6 = { 731f 8b4230 0fb7cb 8b0488 }
            // n = 4, score = 200
            //   731f                 | jae                 0x21
            //   8b4230               | mov                 eax, dword ptr [edx + 0x30]
            //   0fb7cb               | movzx               ecx, bx
            //   8b0488               | mov                 eax, dword ptr [eax + ecx*4]

        $sequence_7 = { 8bf2 8a02 42 84c0 75f9 8dbdf8eeffff }
            // n = 6, score = 200
            //   8bf2                 | mov                 esi, edx
            //   8a02                 | mov                 al, byte ptr [edx]
            //   42                   | inc                 edx
            //   84c0                 | test                al, al
            //   75f9                 | jne                 0xfffffffb
            //   8dbdf8eeffff         | lea                 edi, [ebp - 0x1108]

        $sequence_8 = { 8d45fc 50 6860ea0000 8d45e4 50 6838010000 }
            // n = 6, score = 200
            //   8d45fc               | lea                 eax, [ebp - 4]
            //   50                   | push                eax
            //   6860ea0000           | push                0xea60
            //   8d45e4               | lea                 eax, [ebp - 0x1c]
            //   50                   | push                eax
            //   6838010000           | push                0x138

        $sequence_9 = { 8b7d1c 8b5d18 59 57 53 ff7514 }
            // n = 6, score = 200
            //   8b7d1c               | mov                 edi, dword ptr [ebp + 0x1c]
            //   8b5d18               | mov                 ebx, dword ptr [ebp + 0x18]
            //   59                   | pop                 ecx
            //   57                   | push                edi
            //   53                   | push                ebx
            //   ff7514               | push                dword ptr [ebp + 0x14]

    condition:
        7 of them and filesize < 114688
}

import "pe"

rule win_dispenserxfs_w0 {
    meta:
        description = "Detects ATM Malware DispenserXFS"
        author = "@Xylit0l @r3c0nst / Modified by Florian Roth"
        reference = "https://twitter.com/r3c0nst/status/1100775857306652673"
        date = "2019/02/27"
        score = 80
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.dispenserxfs"
        malpedia_version = "20190307"
        malpedia_license = "CC BY-NC-SA 4.0"
        malpedia_sharing = "TLP:WHITE"

    strings:
        $xc1 = { 68 FF FF 00 00 68 60 EA 00 00 6A 10 }
        $s1 = "\\dispenserXFS.pdb" ascii wide
        $s3 = "C:\\xfsasdf.txt" fullword ascii
        $s4 = "Injected mxsfs killer into %d." fullword ascii
        $s5 = "Waiting for freeze msxfs processes..." fullword ascii

    condition:
        1 of them or pe.imphash() == "617e037ae26d1931818db0790fb44bfe"
}