Analysis of isapnp.sys: clean verdict, risk score 12/100. 0 YARA matches. SHA256 c850ad0e2f290275. Kernel imports, IOCTL codes, MITRE ATT&CK, and code-signing details.
DriverShield analyzed the Windows kernel driver isapnp.sys and assigned a verdict of Clean with a composite risk score of 12/100, indicating no notable risk signals (0-29 band).
| Verdict | Clean (12/100) |
| YARA matches | 0 |
| File size | 24040 bytes |
| Code-signing signer | Microsoft Windows |
| Analyzed | 2026-03-22 |
| SHA256 | c850ad0e2f2902755fa51d7d30d50bf3c251a979daaaae7ac88e4b8795586ac5 |
| SHA1 | 0f1c13b6896f3bdb850d09c3157857795f4f040b |
| MD5 | 3f03ff7629c866783464df26a95a748c |
Version resource data embedded in the isapnp.sys PE header, as extracted by the analysis engine.
| File description | PNP ISA Bus Driver |
|---|---|
| Product | Microsoft® Windows® Operating System |
| Company | Microsoft Corporation |
| Original filename | isapnp.sys |
| Internal name | isapnp.sys |
| File version | 10.0.19041.3636 (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 | 6 / 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 isapnp.sys, ranked by exploitation relevance.
| API | Risk | Why it matters |
|---|---|---|
| IofCompleteRequest | low | Standard kernel API - generally benign |
| KeWaitForSingleObject | low | Standard kernel API - generally benign |
| ZwClose | low | Standard kernel API - generally benign |
| KeInitializeEvent | low | Standard kernel API - generally benign |
| ExAllocatePoolWithTag | low | Standard kernel API - generally benign |
| ZwQueryValueKey | low | Standard kernel API - generally benign |
| KeSetEvent | low | Standard kernel API - generally benign |
| RtlInitUnicodeString | low | Standard kernel API - generally benign |
| IoDeleteDevice | low | Standard kernel API - generally benign |
| IoCreateDevice | 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 |
| 0x00340390 | medium | METHOD_BUFFERED | FILE_DEVICE_DISK Function #228 |
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 | 0x05EA | 0x0600 | 5.66 | CODE, EXEC, READ |
| .rdata | 0x05A0 | 0x0600 | 3.89 | IDATA, READ |
| .data | 0x0228 | 0x0200 | 0.28 | IDATA, READ, WRITE |
| .pdata | 0x0180 | 0x0200 | 3.05 | IDATA, READ |
| .idata | 0x03DC | 0x0400 | 4.16 | IDATA, READ |
| PAGE | 0x0C28 | 0x0E00 | 5.43 | CODE, EXEC, READ |
| INIT | 0x0192 | 0x0200 | 4.67 | CODE, EXEC, READ, DISCARD |
| GFIDS | 0x005C | 0x0200 | 0.83 | IDATA, READ, DISCARD |
| .rsrc | 0x0C00 | 0x0C00 | 3.43 | IDATA, READ, DISCARD |
| .reloc | 0x01A0 | 0x0200 | 3.99 | 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 | System Services: Service Execution | Execution |
| T1652 | Device Driver Discovery | Discovery |
| Signer | Microsoft Windows |
|---|---|
| Signer organisation | Microsoft Corporation |
| Issuer | Microsoft Windows Production PCA 2011 |
| Serial | 330000041331BC198807A90774000000000413 |
| Valid from | 2023-02-03 00:05 UTC |
| Valid until | 2024-02-01 00:05 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, isapnp.sys is assessed as clean, with no notable risk signals. Its composite risk score is 12/100 (verdict: clean). Always validate findings independently before acting.
isapnp.sys has a DriverShield composite risk score of 12/100, placing it in the clean verdict band. SHA256: c850ad0e2f2902755fa51d7d30d50bf3c251a979daaaae7ac88e4b8795586ac5.
isapnp.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