Analysis of msfs.sys: clean verdict, risk score 15/100. 0 YARA matches. SHA256 8ac1a5358691da4f. Kernel imports, IOCTL codes, MITRE ATT&CK, and code-signing details.
DriverShield analyzed the Windows kernel driver msfs.sys and assigned a verdict of Clean with a composite risk score of 15/100, indicating no notable risk signals (0-29 band).
| Verdict | Clean (15/100) |
| YARA matches | 0 |
| File size | 44048 bytes |
| Code-signing signer | Microsoft Windows |
| Analyzed | 2026-03-22 |
| SHA256 | 8ac1a5358691da4fbec7baa3711321ead20439029031696f12bb287771e82893 |
| SHA1 | 17fa53912d7e9cb72d11f7239ce3074aff7914a5 |
| MD5 | 4d8c5c0b06d8f4b28aad865aca6c5494 |
Version resource data embedded in the msfs.sys PE header, as extracted by the analysis engine.
| File description | Mailslot driver |
|---|---|
| Product | Microsoft® Windows® Operating System |
| Company | Microsoft Corporation |
| Original filename | MSFS.SYS |
| Internal name | MSFS.SYS |
| File version | 10.0.19041.1 (WinBuild.160101.0800) |
| Copyright | © Microsoft Corporation. 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 | 0 / 100 |
| Dangerous kernel imports | 39 / 100 |
| IOCTL dispatch surface | 30 / 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 msfs.sys, ranked by exploitation relevance.
| API | Risk | Why it matters |
|---|---|---|
| KeBugCheckEx | medium | Moderate risk - system modification capability |
| SeSinglePrivilegeCheck | low | Standard kernel API - generally benign |
| SeAccessCheck | low | Standard kernel API - generally benign |
| RtlInitUnicodeString | low | Standard kernel API - generally benign |
| IofCompleteRequest | low | Standard kernel API - generally benign |
| KeInitializeEvent | low | Standard kernel API - generally benign |
| ProbeForWrite | low | Standard kernel API - generally benign |
| IoCreateDevice | low | Standard kernel API - generally benign |
| ExAllocatePoolWithTag | low | Standard kernel API - generally benign |
| IoDeleteDevice | 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 |
|---|---|---|---|
| 0x003401C7 | high | METHOD_NEITHER | FILE_DEVICE_DISK Function #113 |
| 0x0080380B | high | METHOD_NEITHER | FILE_DEVICE_CUSTOM Function #3586 |
| 0x0080878B | high | METHOD_NEITHER | FILE_DEVICE_CUSTOM Function #482 |
| 0x002200F0 | medium | METHOD_BUFFERED | FILE_DEVICE_UNKNOWN Function #60 |
| 0x008024AC | medium | METHOD_BUFFERED | FILE_DEVICE_CUSTOM Function #2347 |
| 0x0080248C | medium | METHOD_BUFFERED | FILE_DEVICE_CUSTOM Function #2339 |
| 0x0022E840 | medium | METHOD_BUFFERED | FILE_DEVICE_UNKNOWN Function #2576 |
| 0x0034BB00 | medium | METHOD_BUFFERED | FILE_DEVICE_DISK Function #3776 |
| 0x0080249C | medium | METHOD_BUFFERED | FILE_DEVICE_CUSTOM Function #2343 |
| 0x00340374 | medium | METHOD_BUFFERED | FILE_DEVICE_DISK Function #221 |
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 | 0x0976 | 0x0A00 | 5.66 | CODE, EXEC, READ |
| .rdata | 0x0DC0 | 0x0E00 | 4.79 | IDATA, READ |
| .data | 0x00A8 | 0x0200 | 0.3 | IDATA, READ, WRITE |
| .pdata | 0x063C | 0x0800 | 3.66 | IDATA, READ |
| .idata | 0x0C84 | 0x0E00 | 4.35 | IDATA, READ |
| PAGE | 0x4293 | 0x4400 | 5.95 | CODE, EXEC, READ |
| PAGEDATA | 0x0010 | 0x0000 | 0 | READ, WRITE |
| PAGEDATA | 0x0004 | 0x0200 | 0 | IDATA, READ, WRITE |
| INIT | 0x020D | 0x0400 | 3.44 | CODE, EXEC, READ, DISCARD |
| GFIDS | 0x0064 | 0x0200 | 0.9 | IDATA, READ, DISCARD |
| .rsrc | 0x03E8 | 0x0400 | 3.24 | IDATA, READ, DISCARD |
| .reloc | 0x04C8 | 0x0600 | 4.36 | 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 |
|---|---|---|
| T1071 | Application Layer Protocol | Command and Control |
| T1211 | Exploitation for Defense Evasion | Defense Evasion |
| T1543.003 | Windows Service | Persistence |
| T1553.002 | Subvert Trust Controls: Code Signing | Defense Evasion |
| T1569.002 | Service Execution | Execution |
| T1652 | Device Driver Discovery | Discovery |
| Signer | Microsoft Windows |
|---|---|
| Signer organisation | Microsoft Corporation |
| Issuer | Microsoft Windows Production PCA 2011 |
| Serial | 330000023241FB59996DCC4DFF000000000232 |
| Valid from | 2019-05-02 21:24 UTC |
| Valid until | 2020-05-02 21:24 UTC (expired) |
| Signature validity | Not verified |
Engine angr, status no_findings, 0 paths explored at a maximum depth of 0. Vulnerability classes reached: 0. Exploitable paths: 0.
Based on DriverShield static and dynamic analysis, msfs.sys is assessed as clean, with no notable risk signals. Its composite risk score is 15/100 (verdict: clean). Always validate findings independently before acting.
msfs.sys has a DriverShield composite risk score of 15/100, placing it in the clean verdict band. SHA256: 8ac1a5358691da4fbec7baa3711321ead20439029031696f12bb287771e82893.
msfs.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.
Related: Other drivers signed by Microsoft Windows · What an IOCTL dispatch code is · BYOVD research index · full driver database · CVE library · code signing atlas