KPOT Stealer (Malware Family)

KPOT Stealer

aka: Khalesi, Kpot

VTCollection URLhaus

KPOT is an information-stealing Trojan horse that can steal information from infected computers. It is distributed through phishing emails and malicious websites. Once executed on a computer, KPOT can steal passwords, credit card numbers, and other personal information.

References

2019-05-09 ⋅ Proofpoint ⋅ Dennis Schwarz, Proofpoint Threat Insight Team
New KPOT v2.0 stealer brings zero persistence and in-memory features to silently steal credentials
KPOT Stealer

Yara Rules

[TLP:WHITE] win_kpot_stealer_auto (20260504 | Detects win.kpot_stealer.)

rule win_kpot_stealer_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.kpot_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.kpot_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 = { 83f92f 7414 83f95c 740a 83f962 7560 c60008 }
            // n = 7, score = 500
            //   83f92f               | cmp                 ecx, 0x2f
            //   7414                 | je                  0x16
            //   83f95c               | cmp                 ecx, 0x5c
            //   740a                 | je                  0xc
            //   83f962               | cmp                 ecx, 0x62
            //   7560                 | jne                 0x62
            //   c60008               | mov                 byte ptr [eax], 8

        $sequence_1 = { 57 ff15???????? 8bf8 59 85ff 750c }
            // n = 6, score = 500
            //   57                   | push                edi
            //   ff15????????         |                     
            //   8bf8                 | mov                 edi, eax
            //   59                   | pop                 ecx
            //   85ff                 | test                edi, edi
            //   750c                 | jne                 0xe

        $sequence_2 = { 84c9 75e4 33c0 5f 5e c3 8bc6 }
            // n = 7, score = 500
            //   84c9                 | test                cl, cl
            //   75e4                 | jne                 0xffffffe6
            //   33c0                 | xor                 eax, eax
            //   5f                   | pop                 edi
            //   5e                   | pop                 esi
            //   c3                   | ret                 
            //   8bc6                 | mov                 eax, esi

        $sequence_3 = { 66890c42 40 3bc7 7cec 8b4d08 }
            // n = 5, score = 500
            //   66890c42             | mov                 word ptr [edx + eax*2], cx
            //   40                   | inc                 eax
            //   3bc7                 | cmp                 eax, edi
            //   7cec                 | jl                  0xffffffee
            //   8b4d08               | mov                 ecx, dword ptr [ebp + 8]

        $sequence_4 = { ff4d0c 0f85f7feffff e9???????? 83c770 }
            // n = 4, score = 500
            //   ff4d0c               | dec                 dword ptr [ebp + 0xc]
            //   0f85f7feffff         | jne                 0xfffffefd
            //   e9????????           |                     
            //   83c770               | add                 edi, 0x70

        $sequence_5 = { 8ac3 e8???????? 84c0 7505 8b55f0 eb6b }
            // n = 6, score = 500
            //   8ac3                 | mov                 al, bl
            //   e8????????           |                     
            //   84c0                 | test                al, al
            //   7505                 | jne                 7
            //   8b55f0               | mov                 edx, dword ptr [ebp - 0x10]
            //   eb6b                 | jmp                 0x6d

        $sequence_6 = { 8bf2 81e600001000 0bce c1e914 81e300000600 8bf2 81e600e00100 }
            // n = 7, score = 500
            //   8bf2                 | mov                 esi, edx
            //   81e600001000         | and                 esi, 0x100000
            //   0bce                 | or                  ecx, esi
            //   c1e914               | shr                 ecx, 0x14
            //   81e300000600         | and                 ebx, 0x60000
            //   8bf2                 | mov                 esi, edx
            //   81e600e00100         | and                 esi, 0x1e000

        $sequence_7 = { 894604 85c0 741b 50 e8???????? }
            // n = 5, score = 500
            //   894604               | mov                 dword ptr [esi + 4], eax
            //   85c0                 | test                eax, eax
            //   741b                 | je                  0x1d
            //   50                   | push                eax
            //   e8????????           |                     

        $sequence_8 = { 250f0f0f0f 33d0 c1e004 33c8 8bc2 }
            // n = 5, score = 500
            //   250f0f0f0f           | and                 eax, 0xf0f0f0f
            //   33d0                 | xor                 edx, eax
            //   c1e004               | shl                 eax, 4
            //   33c8                 | xor                 ecx, eax
            //   8bc2                 | mov                 eax, edx

        $sequence_9 = { 59 8b4dfc 8345fc04 817df8???????? }
            // n = 4, score = 500
            //   59                   | pop                 ecx
            //   8b4dfc               | mov                 ecx, dword ptr [ebp - 4]
            //   8345fc04             | add                 dword ptr [ebp - 4], 4
            //   817df8????????       |                     

    condition:
        7 of them and filesize < 219136
}

[TLP:WHITE] win_kpot_stealer_w0 (20190106 | Kpot)

rule win_kpot_stealer_w0 {
    meta:
        description = "Kpot"
        type = "Stealer"
        author = "Fumik0_"
        date = "30/08/2018"

        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.kpot_stealer"
        malpedia_version = "20190106"
        malpedia_license = "CC BY-NC-SA 4.0"
        malpedia_sharing = "TLP:WHITE"
    strings:
        $mz = { 4d 5a }

        // Variant 1
        $v1_s1 = "GET %s HTTP/1.1" wide ascii
        $v1_s2 = "Host: %s" wide ascii
        $v1_s3 = "%02d-%02d-%02d %d:%02d:%02d" wide ascii
        $v1_s4 = "%S/base64.php?_f=%S" wide ascii      
        $v1_s5 = "IP: %S" wide ascii
        $v1_s6 = "MachineGuid: %s" wide ascii
        $v1_s7 = "CPU: %S (%d cores)" wide ascii
        $v1_s8 = "RAM: %S MB" wide ascii
        $v1_s9 = "Screen: %dx%d" wide ascii
        $v1_s10 = "PC: %s" wide ascii
        $v1_s11 = "User: %s" wide ascii
        $v1_s12 = "LT: %S (UTC+%d:%d)" wide ascii
        $v1_s13 = "GPU:" wide ascii
        $v1_s14 = "regbot.php" wide ascii
        $v1_s15 = "ip.php" wide ascii

        // Variant 2
        $v2_s1 = "GET %s HTTP/1.1" wide ascii
        $v2_s2 = "%s/%s.php" wide ascii
        $v2_s3 = "%s/gate.php" wide ascii
        $v2_s4 = "RAM: %s MB" wide ascii
        $v2_s5 = "IP: %s" wide ascii
        $v2_s6 = "CPU: %s (%d cores)" wide ascii
        $v2_s7 = "RAM: %s MB" wide ascii
        $v2_s8 = "Screen: %dx%d" wide ascii
        $v2_s9 = "LT: %s (UTC+%d:%d)" wide ascii
        $v2_s10 = "GPU:" wide ascii
        $v2_s11 = "screen.png" wide ascii

    condition:
        ($mz at 0) and ( (all of ($v1_*)) or (all of ($v2_*)) )
}

Download all Yara Rules

KPOT Stealer Propose Change

References

Yara Rules

KPOT Stealer