rule win_pss_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2023-01-25"
        version = "1"
        description = "Detects win.pss."
        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.pss"
        malpedia_rule_date = "20230124"
        malpedia_hash = "2ee0eebba83dce3d019a90519f2f972c0fcf9686"
        malpedia_version = "20230125"
        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 = { 8d48fe e8???????? e9???????? 83f811 }
            // n = 4, score = 300
            //   8d48fe               | lea                 ecx, [eax - 2]
            //   e8????????           |                     
            //   e9????????           |                     
            //   83f811               | cmp                 eax, 0x11

        $sequence_1 = { 7437 ff15???????? 3de5030000 752a }
            // n = 4, score = 300
            //   7437                 | je                  0x39
            //   ff15????????         |                     
            //   3de5030000           | cmp                 eax, 0x3e5
            //   752a                 | jne                 0x2c

        $sequence_2 = { ff15???????? 83ceff 3bc6 7504 }
            // n = 4, score = 300
            //   ff15????????         |                     
            //   83ceff               | or                  esi, 0xffffffff
            //   3bc6                 | cmp                 eax, esi
            //   7504                 | jne                 6

        $sequence_3 = { 8930 e8???????? 56 57 }
            // n = 4, score = 200
            //   8930                 | mov                 dword ptr [eax], esi
            //   e8????????           |                     
            //   56                   | push                esi
            //   57                   | push                edi

        $sequence_4 = { 6a00 6a00 50 ff15???????? 6a00 6a01 8d4dc0 }
            // n = 7, score = 200
            //   6a00                 | push                0
            //   6a00                 | push                0
            //   50                   | push                eax
            //   ff15????????         |                     
            //   6a00                 | push                0
            //   6a01                 | push                1
            //   8d4dc0               | lea                 ecx, [ebp - 0x40]

        $sequence_5 = { 33ff 57 57 8bf1 52 ff36 }
            // n = 6, score = 200
            //   33ff                 | xor                 edi, edi
            //   57                   | push                edi
            //   57                   | push                edi
            //   8bf1                 | mov                 esi, ecx
            //   52                   | push                edx
            //   ff36                 | push                dword ptr [esi]

        $sequence_6 = { 807dd001 751b 8b55dc 57 ff75d4 8bce e8???????? }
            // n = 7, score = 200
            //   807dd001             | cmp                 byte ptr [ebp - 0x30], 1
            //   751b                 | jne                 0x1d
            //   8b55dc               | mov                 edx, dword ptr [ebp - 0x24]
            //   57                   | push                edi
            //   ff75d4               | push                dword ptr [ebp - 0x2c]
            //   8bce                 | mov                 ecx, esi
            //   e8????????           |                     

        $sequence_7 = { 57 6a01 8d4de4 a3???????? e8???????? a1???????? }
            // n = 6, score = 200
            //   57                   | push                edi
            //   6a01                 | push                1
            //   8d4de4               | lea                 ecx, [ebp - 0x1c]
            //   a3????????           |                     
            //   e8????????           |                     
            //   a1????????           |                     

        $sequence_8 = { 6685c0 740c 668903 4883c302 48ffc9 }
            // n = 5, score = 100
            //   6685c0               | jns                 8
            //   740c                 | dec                 eax
            //   668903               | test                ecx, ecx
            //   4883c302             | test                ax, ax
            //   48ffc9               | je                  0x11

        $sequence_9 = { 4885c0 7447 48c74424680f000000 4889742460 c644245000 803800 7505 }
            // n = 7, score = 100
            //   4885c0               | dec                 eax
            //   7447                 | dec                 ecx
            //   48c74424680f000000     | dec    eax
            //   4889742460           | lea                 edx, [0x1c25a]
            //   c644245000           | dec                 eax
            //   803800               | lea                 ecx, [esp + 0x30]
            //   7505                 | mov                 ebx, eax

        $sequence_10 = { 498d7001 48b8feffffffffffff7f 483bf0 0f87c8000000 483bce }
            // n = 5, score = 100
            //   498d7001             | dec                 ecx
            //   48b8feffffffffffff7f     | lea    esi, [eax + 1]
            //   483bf0               | dec                 eax
            //   0f87c8000000         | mov                 eax, 0xfffffffe
            //   483bce               | ja                  0xce

        $sequence_11 = { 7906 ff15???????? 488b0d???????? 4885c9 }
            // n = 4, score = 100
            //   7906                 | dec                 eax
            //   ff15????????         |                     
            //   488b0d????????       |                     
            //   4885c9               | cmp                 ecx, esi

        $sequence_12 = { 488d155ac20100 488d4c2430 ff15???????? 8bd8 }
            // n = 4, score = 100
            //   488d155ac20100       | mov                 word ptr [ebx], ax
            //   488d4c2430           | dec                 eax
            //   ff15????????         |                     
            //   8bd8                 | add                 ebx, 2

    condition:
        7 of them and filesize < 421888
}