rule win_elise_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.elise."
        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.elise"
        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???????? 85c0 0f8484000000 53 57 }
            // n = 5, score = 400
            //   e8????????           |                     
            //   85c0                 | test                eax, eax
            //   0f8484000000         | je                  0x8a
            //   53                   | push                ebx
            //   57                   | push                edi

        $sequence_1 = { 8b01 294104 8b5104 8bf2 c1ee1f f7de }
            // n = 6, score = 400
            //   8b01                 | mov                 eax, dword ptr [ecx]
            //   294104               | sub                 dword ptr [ecx + 4], eax
            //   8b5104               | mov                 edx, dword ptr [ecx + 4]
            //   8bf2                 | mov                 esi, edx
            //   c1ee1f               | shr                 esi, 0x1f
            //   f7de                 | neg                 esi

        $sequence_2 = { 8901 8b4108 8b5008 56 8b30 }
            // n = 5, score = 400
            //   8901                 | mov                 dword ptr [ecx], eax
            //   8b4108               | mov                 eax, dword ptr [ecx + 8]
            //   8b5008               | mov                 edx, dword ptr [eax + 8]
            //   56                   | push                esi
            //   8b30                 | mov                 esi, dword ptr [eax]

        $sequence_3 = { 5f c3 56 be4d5a0000 663931 7534 }
            // n = 6, score = 400
            //   5f                   | pop                 edi
            //   c3                   | ret                 
            //   56                   | push                esi
            //   be4d5a0000           | mov                 esi, 0x5a4d
            //   663931               | cmp                 word ptr [ecx], si
            //   7534                 | jne                 0x36

        $sequence_4 = { 034e0c 0111 8b7dfc 47 3b7df8 897dfc 7cc6 }
            // n = 7, score = 400
            //   034e0c               | add                 ecx, dword ptr [esi + 0xc]
            //   0111                 | add                 dword ptr [ecx], edx
            //   8b7dfc               | mov                 edi, dword ptr [ebp - 4]
            //   47                   | inc                 edi
            //   3b7df8               | cmp                 edi, dword ptr [ebp - 8]
            //   897dfc               | mov                 dword ptr [ebp - 4], edi
            //   7cc6                 | jl                  0xffffffc8

        $sequence_5 = { 7cf5 33c9 888f00010000 888f01010000 8bf7 }
            // n = 5, score = 400
            //   7cf5                 | jl                  0xfffffff7
            //   33c9                 | xor                 ecx, ecx
            //   888f00010000         | mov                 byte ptr [edi + 0x100], cl
            //   888f01010000         | mov                 byte ptr [edi + 0x101], cl
            //   8bf7                 | mov                 esi, edi

        $sequence_6 = { c1e006 8d5828 c745f406000000 8d0433 8d0447 }
            // n = 5, score = 400
            //   c1e006               | shl                 eax, 6
            //   8d5828               | lea                 ebx, [eax + 0x28]
            //   c745f406000000       | mov                 dword ptr [ebp - 0xc], 6
            //   8d0433               | lea                 eax, [ebx + esi]
            //   8d0447               | lea                 eax, [edi + eax*2]

        $sequence_7 = { 66894202 57 8bc3 c1e310 }
            // n = 4, score = 400
            //   66894202             | mov                 word ptr [edx + 2], ax
            //   57                   | push                edi
            //   8bc3                 | mov                 eax, ebx
            //   c1e310               | shl                 ebx, 0x10

        $sequence_8 = { 8b481c 8b5814 03ca 33d2 42 2b5010 7816 }
            // n = 7, score = 400
            //   8b481c               | mov                 ecx, dword ptr [eax + 0x1c]
            //   8b5814               | mov                 ebx, dword ptr [eax + 0x14]
            //   03ca                 | add                 ecx, edx
            //   33d2                 | xor                 edx, edx
            //   42                   | inc                 edx
            //   2b5010               | sub                 edx, dword ptr [eax + 0x10]
            //   7816                 | js                  0x18

        $sequence_9 = { d1e8 33c2 eb02 d1e8 4e 75f1 }
            // n = 6, score = 300
            //   d1e8                 | shr                 eax, 1
            //   33c2                 | xor                 eax, edx
            //   eb02                 | jmp                 4
            //   d1e8                 | shr                 eax, 1
            //   4e                   | dec                 esi
            //   75f1                 | jne                 0xfffffff3

        $sequence_10 = { 8b7df4 8d4e01 81e1ff000080 7908 49 81c900ffffff }
            // n = 6, score = 300
            //   8b7df4               | mov                 edi, dword ptr [ebp - 0xc]
            //   8d4e01               | lea                 ecx, [esi + 1]
            //   81e1ff000080         | and                 ecx, 0x800000ff
            //   7908                 | jns                 0xa
            //   49                   | dec                 ecx
            //   81c900ffffff         | or                  ecx, 0xffffff00

        $sequence_11 = { 46 4f 75eb f7d0 }
            // n = 4, score = 300
            //   46                   | inc                 esi
            //   4f                   | dec                 edi
            //   75eb                 | jne                 0xffffffed
            //   f7d0                 | not                 eax

        $sequence_12 = { 8a8800010000 8a9001010000 0f8e93000000 53 }
            // n = 4, score = 300
            //   8a8800010000         | mov                 cl, byte ptr [eax + 0x100]
            //   8a9001010000         | mov                 dl, byte ptr [eax + 0x101]
            //   0f8e93000000         | jle                 0x99
            //   53                   | push                ebx

        $sequence_13 = { 83c8ff b9ff000000 83ff08 0f82a1000000 8bd7 }
            // n = 5, score = 300
            //   83c8ff               | or                  eax, 0xffffffff
            //   b9ff000000           | mov                 ecx, 0xff
            //   83ff08               | cmp                 edi, 8
            //   0f82a1000000         | jb                  0xa7
            //   8bd7                 | mov                 edx, edi

        $sequence_14 = { 0145f0 6a00 6800010000 ff75ec 1155f4 }
            // n = 5, score = 300
            //   0145f0               | add                 dword ptr [ebp - 0x10], eax
            //   6a00                 | push                0
            //   6800010000           | push                0x100
            //   ff75ec               | push                dword ptr [ebp - 0x14]
            //   1155f4               | adc                 dword ptr [ebp - 0xc], edx

        $sequence_15 = { 0fb6d2 03d7 81e2ff000080 7908 4a 81ca00ffffff 42 }
            // n = 7, score = 300
            //   0fb6d2               | movzx               edx, dl
            //   03d7                 | add                 edx, edi
            //   81e2ff000080         | and                 edx, 0x800000ff
            //   7908                 | jns                 0xa
            //   4a                   | dec                 edx
            //   81ca00ffffff         | or                  edx, 0xffffff00
            //   42                   | inc                 edx

    condition:
        7 of them and filesize < 204800
}

rule win_elise_w0 {
    meta:
        author = "ThreatConnect Intelligence Research Team - Wes Hurd"
        license = "Usage of this signature is subject to the ThreatConnect Terms of Service, which are incorporated herein by reference."
        source = "https://github.com/mattulm/sfiles_yara/blob/master/malware/Elise.yar"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.elise"
        malpedia_version = "20170517"
        malpedia_license = "CC BY-NC-SA 4.0"
        malpedia_sharing = "TLP:WHITE"
    strings:
        $0E = "\\000ELISEA"
        $D = "~DF37382D8F2E.tmp" nocase wide ascii
        $SE = "SetElise.pdb" wide ascii
        $xpage = "/%x/page_%02d%02d%02d%02d.html" wide ascii
    condition:
        any of them
}