Analysis of KKYUM.sys: suspicious verdict, risk score 58/100. 0 YARA matches, 16/75 multi-engine detections. SHA256 72bd55f4459c992b. Kernel imports, IOCTL codes, MITRE ATT&CK, and code-signing details.
DriverShield analyzed the Windows kernel driver KKYUM.sys and assigned a verdict of Suspicious with a composite risk score of 58/100, indicating some risk signals warranting review (30-59 band).
| Verdict | Suspicious (58/100) |
| YARA matches | 0 |
| Multi-engine detections | 16 / 75 |
| File size | 26768 bytes |
| Code-signing signer | Microsoft Windows Hardware Compatibility Publisher |
| Analyzed | 2026-09-06 |
| SHA256 | 72bd55f4459c992b9caa1a33cb6862f1f3085ca35839c58dee8b75db22ca605f |
| SHA1 | 4d0708b4a6adee830c30b72add84172fb62fd049 |
| MD5 | 8516410b49bb79c08c19a37c516dad72 |
Each component is scored 0-100 and then weighted into the composite. See the analysis methodology for the exact formula.
| Component | Sub-score |
|---|---|
| Multi-engine consensus | 0 / 100 |
| YARA signature matches | 0 / 100 |
| Dangerous kernel imports | 100 / 100 |
| IOCTL dispatch surface | 21 / 100 |
| Known-vulnerable corpus | 100 / 100 |
| Code-signing state | 80 / 100 |
| Packing and entropy | 0 / 100 |
| Dynamic behaviour | 0 / 100 |
| CVE cross-reference | 0 / 100 |
Kernel-mode APIs resolved from the Import Address Table of KKYUM.sys, ranked by exploitation relevance.
| API | Risk | Why it matters |
|---|---|---|
| MmCopyVirtualMemory | critical | Highly dangerous - potential for arbitrary code execution, memory corruption, or process termination |
| MmMapLockedPagesSpecifyCache | critical | Highly dangerous - potential for arbitrary code execution, memory corruption, or process termination |
| PsLookupProcessByProcessId | high | Potentially dangerous - could be used for privilege escalation or security bypass |
| ZwQuerySystemInformation | medium | Moderate risk - system modification capability |
| IoDeleteDevice | low | Standard kernel API - generally benign |
| IoCreateDevice | low | Standard kernel API - generally benign |
| ExAllocatePoolWithTag | low | Standard kernel API - generally benign |
| IoCreateSymbolicLink | low | Standard kernel API - generally benign |
| IofCompleteRequest | low | Standard kernel API - generally benign |
| ExAllocatePool | low | Standard kernel API - generally benign |
| RtlInitUnicodeString | low | Standard kernel API - generally benign |
| DbgPrintEx | low | Standard kernel API - generally benign |
| IoDeleteSymbolicLink | low | Standard kernel API - generally benign |
Control codes reachable through the driver dispatch routine. Codes tied to published exploit code are flagged, since they are the primary Bring Your Own Vulnerable Driver (BYOVD) entry points.
| Code | Severity | Transfer | Description |
|---|---|---|---|
| 0x002200F0 | medium | METHOD_BUFFERED | FILE_DEVICE_UNKNOWN Function #60 |
| 0x0034BF1D | medium | METHOD_IN_DIRECT | FILE_DEVICE_DISK Function #4039 |
| 0x0022B805 | medium | METHOD_IN_DIRECT | FILE_DEVICE_UNKNOWN Function #3585 |
| 0x0022C715 | medium | METHOD_IN_DIRECT | FILE_DEVICE_UNKNOWN Function #453 |
| 0x0022D315 | medium | METHOD_IN_DIRECT | FILE_DEVICE_UNKNOWN Function #1221 |
| 0x0022A305 | medium | METHOD_IN_DIRECT | FILE_DEVICE_UNKNOWN Function #2241 |
| 0x00340030 | medium | METHOD_BUFFERED | FILE_DEVICE_DISK Function #12 |
Section layout and Shannon entropy. High entropy in a code section is a packing or encryption indicator.
| Section | Virtual size | Raw size | Entropy | Flags |
|---|---|---|---|---|
| .text | 0x25E0 | 0x2600 | 6.29 | CODE, EXEC, READ |
| .rdata | 0x0B80 | 0x0C00 | 4.58 | IDATA, READ |
| .data | 0x04E0 | 0x0200 | 0.82 | IDATA, READ, WRITE |
| .pdata | 0x01F8 | 0x0200 | 3.98 | IDATA, READ |
| INIT | 0x04F4 | 0x0600 | 4.33 | CODE, EXEC, READ, DISCARD |
| .reloc | 0x0038 | 0x0200 | 0.69 | IDATA, READ, DISCARD |
| Control Flow Guard | Enabled |
|---|---|
| ASLR | Enabled |
| DEP | Enabled |
| Integrity check | Not enforced |
| Mitigation score | 85 / 100 |
Techniques this driver could enable if loaded by an adversary.
| ID | Technique | Tactic |
|---|---|---|
| T1003 | OS Credential Dumping | Credential Access |
| T1003.001 | OS Credential Dumping: LSASS Memory | Credential Access |
| T1006 | Direct Volume Access | Defense Evasion |
| T1055.001 | Process Injection: DLL Injection | Defense Evasion |
| T1055.012 | Process Hollowing | Defense Evasion |
| T1068 | Exploitation for Privilege Escalation | Privilege Escalation |
| T1211 | Exploitation for Defense Evasion | Defense Evasion |
| T1489 | Service Stop | Impact |
| T1543.003 | Windows Service | Persistence |
| T1553.002 | Subvert Trust Controls: Code Signing | Defense Evasion |
| T1562.001 | Impair Defenses | Defense Evasion |
| T1569.002 | Service Execution | Execution |
| T1652 | Device Driver Discovery | Discovery |
| Signer | Microsoft Windows Hardware Compatibility Publisher |
|---|---|
| Signer organisation | Microsoft Corporation |
| Issuer | Microsoft Windows Third Party Component CA 2012 |
| Serial | 3300000124E76F6CA813A27C35000000000124 |
| Valid from | 2025-02-20 20:08 UTC |
| Valid until | 2026-02-18 20:08 UTC (expired) |
| Signature validity | Not verified |
Engine angr, status completed, 42 paths explored at a maximum depth of 42. Vulnerability classes reached: 1. Exploitable paths: 0.
Corpus match: this hash is present in the known-vulnerable driver corpus DriverShield cross-references during analysis, which is why the score carries a full weighting on that component.
Based on DriverShield static and dynamic analysis, KKYUM.sys shows some suspicious signals and warrants manual review. Its composite risk score is 58/100 (verdict: suspicious). Always validate findings independently before acting.
KKYUM.sys has a DriverShield composite risk score of 58/100, placing it in the suspicious verdict band. SHA256: 72bd55f4459c992b9caa1a33cb6862f1f3085ca35839c58dee8b75db22ca605f.
KKYUM.sys is a Windows kernel-mode driver (.sys) analyzed by DriverShield for vulnerabilities, BYOVD abuse potential, and malware indicators. It is code-signed by Microsoft Windows Hardware Compatibility Publisher.
Related: Other drivers signed by Microsoft Windows Hardware Compatibility Publisher · What an IOCTL dispatch code is · BYOVD research index · full driver database · CVE library · code signing atlas