Analysis of portwell.sys: suspicious verdict, risk score 58/100. 2 YARA matches, 0/68 multi-engine detections. SHA256 2f0b16ed90b8c15b. Kernel imports, IOCTL codes, MITRE ATT&CK, and code-signing details.
DriverShield analyzed the Windows kernel driver portwell.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 | 2 |
| Multi-engine detections | 0 / 68 |
| File size | 16848 bytes |
| Code-signing signer | Certum Time-Stamping Authority |
| Analyzed | 2026-04-02 |
| SHA256 | 2f0b16ed90b8c15bf52a7c32699dbe0dbcd38fc02ed2ddb4e1ba35487177b6c5 |
| SHA1 | a7b72d8a1751a10643c1cc1c148175ca13bcbebe |
| MD5 | a93b28348e04109cc186b985c9308295 |
Version resource data embedded in the portwell.sys PE header, as extracted by the analysis engine.
| File description | kernel mode driver |
|---|---|
| Product | portwell driver |
| Company | Portwell Inc. |
| Original filename | portwell.sys |
| Internal name | portwell.sys |
| File version | 0.1.0.0 |
| Copyright | Copyright (C) 2010 Portwell All rights reserved. |
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 | 80 / 100 |
| Dangerous kernel imports | 100 / 100 |
| IOCTL dispatch surface | 9 / 100 |
| Known-vulnerable corpus | 0 / 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 portwell.sys, ranked by exploitation relevance.
| API | Risk | Why it matters |
|---|---|---|
| MmMapIoSpace | critical | Highly dangerous - potential for arbitrary code execution, memory corruption, or process termination |
| HalGetBusDataByOffset | high | Potentially dangerous - could be used for privilege escalation or security bypass |
| HalSetBusDataByOffset | high | Potentially dangerous - could be used for privilege escalation or security bypass |
| MmUnmapIoSpace | medium | Moderate risk - system modification capability |
| KeBugCheckEx | medium | Moderate risk - system modification capability |
| IofCompleteRequest | low | Standard kernel API - generally benign |
| IoDeleteSymbolicLink | low | Standard kernel API - generally benign |
| IoDeleteDevice | low | Standard kernel API - generally benign |
| IoCreateDevice | low | Standard kernel API - generally benign |
| RtlInitUnicodeString | low | Standard kernel API - generally benign |
| IoCreateSymbolicLink | low | Standard kernel API - generally benign |
| DbgPrint | 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 |
| 0x0080248C | medium | METHOD_BUFFERED | FILE_DEVICE_CUSTOM Function #2339 |
| 0x00340344 | medium | METHOD_BUFFERED | FILE_DEVICE_DISK Function #209 |
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 | 0x1275 | 0x1400 | 5.3 | CODE, EXEC, READ |
| .rdata | 0x01C0 | 0x0200 | 3.6 | IDATA, READ |
| .data | 0x0114 | 0x0200 | 0.3 | IDATA, READ, WRITE |
| .pdata | 0x0144 | 0x0200 | 2.49 | IDATA, READ |
| INIT | 0x026A | 0x0400 | 3.46 | CODE, EXEC, READ, WRITE, DISCARD |
| .rsrc | 0x03A8 | 0x0400 | 2.98 | IDATA, READ, DISCARD |
| Control Flow Guard | Not enabled |
|---|---|
| ASLR | Not enabled |
| DEP | Not enabled |
| Integrity check | Not enforced |
| Mitigation score | 5 / 100 |
| Rule | Severity | Detects |
|---|---|---|
| BYOVD_MemRW | critical | Phys memory mapping + device creation |
| SUSP_PhysMem | high | Physical memory mapping |
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 |
| T1014 | Rootkit | Defense Evasion |
| T1055.012 | Process Hollowing | Defense Evasion |
| T1068 | Exploitation for Privilege Escalation | Privilege Escalation |
| T1071 | Application Layer Protocol | Command and Control |
| T1542.001 | Pre-OS Boot: System Firmware | Persistence |
| T1543.003 | Windows Service | Persistence |
| T1569.002 | Service Execution | Execution |
| T1601 | Modify System Image | Defense Evasion |
| T1652 | Device Driver Discovery | Discovery |
| Signer | Certum Time-Stamping Authority |
|---|---|
| Signer organisation | Unizeto Technologies S.A. |
| Issuer | Certum CA |
| Serial | 47A55 |
| Valid from | 2009-03-03 12:58 UTC |
| Valid until | 2024-03-03 12:58 UTC (expired) |
| Signature validity | Not verified |
Engine angr, status completed, 19 paths explored at a maximum depth of 19. Vulnerability classes reached: 1. Exploitable paths: 0.
Based on DriverShield static and dynamic analysis, portwell.sys shows some suspicious signals and warrants manual review. Its composite risk score is 58/100 (verdict: suspicious). Always validate findings independently before acting.
portwell.sys has a DriverShield composite risk score of 58/100, placing it in the suspicious verdict band. SHA256: 2f0b16ed90b8c15bf52a7c32699dbe0dbcd38fc02ed2ddb4e1ba35487177b6c5.
portwell.sys is a Windows kernel-mode driver (.sys) analyzed by DriverShield for vulnerabilities, BYOVD abuse potential, and malware indicators. It is code-signed by Certum Time-Stamping Authority.
Related: Other drivers signed by Certum Time-Stamping Authority · What an IOCTL dispatch code is · How YARA matching feeds the score · BYOVD research index · full driver database · CVE library · code signing atlas