acpi.sys - Suspicious (58/100) - DriverShield Analysis

Analysis of acpi.sys: suspicious verdict, risk score 58/100. 2 YARA matches, 0/74 multi-engine detections. SHA256 67d6b8d7b0fd4e35. Kernel imports, IOCTL codes, MITRE ATT&CK, and code-signing details.

acpi.sys - Analysis Report

DriverShield analyzed the Windows kernel driver acpi.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 / 74
File size	873960 bytes
Code-signing signer	Microsoft Windows
Analyzed	2026-07-19
SHA256	67d6b8d7b0fd4e356bcfa060e0862f9fca51ad541488c62891d55d97bbd9a5cc
SHA1	2de878614ae76c1e4b86b8fb87d80fb9f3d308a4
MD5	8cf3b7fb06b77ad8456e6a075fce25b0

Driver identity

Version resource data embedded in the acpi.sys PE header, as extracted by the analysis engine.

File description	ACPI Driver for NT
Product	Microsoft® Windows® Operating System
Company	Microsoft Corporation
Original filename	ACPI.sys
Internal name	ACPI.sys
File version	10.0.26100.8521 (WinBuild.160101.0800)
Copyright	© Microsoft Corporation. All rights reserved.

How the 58/100 score breaks down

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	100 / 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 imports (32)

Kernel-mode APIs resolved from the Import Address Table of acpi.sys, ranked by exploitation relevance.

API	Risk	Why it matters
HalSetBusDataByOffset	high	Potentially dangerous - could be used for privilege escalation or security bypass
HalGetBusDataByOffset	high	Potentially dangerous - could be used for privilege escalation or security bypass
MmGetSystemRoutineAddress	high	Potentially dangerous - could be used for privilege escalation or security bypass
ZwSetSystemInformation	high	Potentially dangerous - could be used for privilege escalation or security bypass
MmGetPhysicalAddress	high	Potentially dangerous - could be used for privilege escalation or security bypass
KeBugCheckEx	medium	Moderate risk - system modification capability
IoGetDeviceObjectPointer	medium	Moderate risk - system modification capability
ZwQuerySystemInformation	medium	Moderate risk - system modification capability
ObReferenceObjectByHandle	medium	Moderate risk - system modification capability
ZwCreateKey	medium	Moderate risk - system modification capability
MmUnmapIoSpace	medium	Moderate risk - system modification capability
ZwSetValueKey	medium	Moderate risk - system modification capability
KeWaitForSingleObject	low	Standard kernel API - generally benign
IofCompleteRequest	low	Standard kernel API - generally benign
IoDeleteDevice	low	Standard kernel API - generally benign
ZwClose	low	Standard kernel API - generally benign
ExAllocatePool2	low	Standard kernel API - generally benign
KeSetEvent	low	Standard kernel API - generally benign
IoDeleteSymbolicLink	low	Standard kernel API - generally benign
KeInitializeEvent	low	Standard kernel API - generally benign
ZwOpenFile	low	Standard kernel API - generally benign
DbgPrintEx	low	Standard kernel API - generally benign
IoCreateDevice	low	Standard kernel API - generally benign
IoBuildDeviceIoControlRequest	low	Standard kernel API - generally benign
ZwOpenKey	low	Standard kernel API - generally benign
ZwQueryValueKey	low	Standard kernel API - generally benign
SeSinglePrivilegeCheck	low	Standard kernel API - generally benign
ZwCreateFile	low	Standard kernel API - generally benign

Showing the 28 highest-relevance imports of 32 resolved.

IOCTL dispatch codes (40)

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
0x002283FF	high	METHOD_NEITHER	FILE_DEVICE_UNKNOWN Function #255
0x008005BF	high	METHOD_NEITHER	FILE_DEVICE_CUSTOM Function #367
0x008004FB	high	METHOD_NEITHER	FILE_DEVICE_CUSTOM Function #318
0x008000FB	high	METHOD_NEITHER	FILE_DEVICE_CUSTOM Function #62
0x008003FB	high	METHOD_NEITHER	FILE_DEVICE_CUSTOM Function #254
0x008004BB	high	METHOD_NEITHER	FILE_DEVICE_CUSTOM Function #302
0x0080850F	high	METHOD_NEITHER	FILE_DEVICE_CUSTOM Function #323
0x008004FF	high	METHOD_NEITHER	FILE_DEVICE_CUSTOM Function #319
0x008004BF	high	METHOD_NEITHER	FILE_DEVICE_CUSTOM Function #303
0x0080584F	high	METHOD_NEITHER	FILE_DEVICE_CUSTOM Function #1555
0x0080808B	high	METHOD_NEITHER	FILE_DEVICE_CUSTOM Function #34
0x0080818B	high	METHOD_NEITHER	FILE_DEVICE_CUSTOM Function #98
0x0022E8CF	high	METHOD_NEITHER	FILE_DEVICE_UNKNOWN Function #2611
0x0080840F	high	METHOD_NEITHER	FILE_DEVICE_CUSTOM Function #259
0x0080880F	high	METHOD_NEITHER	FILE_DEVICE_CUSTOM Function #515
0x0080830F	high	METHOD_NEITHER	FILE_DEVICE_CUSTOM Function #195
0x008007C7	high	METHOD_NEITHER	FILE_DEVICE_CUSTOM Function #497
0x00343043	high	METHOD_NEITHER	FILE_DEVICE_DISK Function #3088
0x0034541F	high	METHOD_NEITHER	FILE_DEVICE_DISK Function #1287
0x00223413	high	METHOD_NEITHER	FILE_DEVICE_UNKNOWN Function #3332
0x0022641F	high	METHOD_NEITHER	FILE_DEVICE_UNKNOWN Function #2311
0x00226427	high	METHOD_NEITHER	FILE_DEVICE_UNKNOWN Function #2313
0x00225417	high	METHOD_NEITHER	FILE_DEVICE_UNKNOWN Function #1285
0x00226423	high	METHOD_NEITHER	FILE_DEVICE_UNKNOWN Function #2312

Showing 24 of 40 extracted control codes.

PE sections

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	0x705A7	0x71000	6.32	CODE, EXEC, READ
fothk	0x1000	0x1000	0.03	CODE, EXEC, READ
.rdata	0x116F0	0x12000	5.65	IDATA, READ
.data	0x6688	0x4000	2.38	IDATA, READ, WRITE
.pdata	0x5FDC	0x6000	5.98	IDATA, READ
.idata	0x3232	0x4000	4.14	IDATA, READ
PAGE	0x2BB15	0x2C000	6.43	CODE, EXEC, READ
.edata	0x0077	0x1000	0.26	IDATA, READ
PAGECONS	0x0BE0	0x1000	2.86	IDATA, READ
INIT	0x589A	0x6000	6.16	CODE, EXEC, READ, DISCARD
GFIDS	0x0C40	0x1000	3.8	IDATA, READ, DISCARD
.rsrc	0x4498	0x5000	3.62	IDATA, READ, DISCARD
.reloc	0x5A2C	0x6000	5.9	IDATA, READ, DISCARD

Exploit mitigations

Control Flow Guard	Enabled
ASLR	Enabled
DEP	Enabled
Integrity check	Not enforced
Mitigation score	85 / 100

CFG Enabled - Control Flow Guard is active - indirect calls are validated against a bitmap of valid targets at runtime.
ASLR Enabled - Address Space Layout Randomization is active - base address is randomized on each load.
DEP/NX Enabled - Data Execution Prevention is active - non-executable pages cannot be executed.
Expired Certificate - The driver is signed but the certificate has expired. Windows may still load it depending on revocation policy.

YARA rule matches (2)

Rule	Severity	Detects
BYOVD_MemRW	critical	Phys memory mapping + device creation
SUSP_PhysMem	high	Physical memory mapping

MITRE ATT&CK techniques (14)

Techniques this driver could enable if loaded by an adversary.

ID	Technique	Tactic
T1003.001	OS Credential Dumping: LSASS Memory	Credential Access
T1014	Rootkit	Defense Evasion
T1055.012	Process Hollowing	Defense Evasion
T1068	Exploitation for Privilege Escalation	Privilege Escalation
T1071	Application Layer Protocol	Command and Control
T1112	Modify Registry	Defense Evasion
T1211	Exploitation for Defense Evasion	Defense Evasion
T1542.001	Pre-OS Boot: System Firmware	Persistence
T1543.003	Windows Service	Persistence
T1547.001	Registry Run Keys	Persistence
T1553.002	Subvert Trust Controls: Code Signing	Defense Evasion
T1569.002	Service Execution	Execution
T1601	Modify System Image	Defense Evasion
T1652	Device Driver Discovery	Discovery

Code-signing chain

Signer	Microsoft Windows
Signer organisation	Microsoft Corporation
Issuer	Microsoft Windows Production PCA 2011
Serial	3300000518418419ADCBAD294F000000000518
Valid from	2025-06-19 18:11 UTC
Valid until	2026-06-17 18:11 UTC (expired)
Signature validity	Not verified

Certificate revision: 0x0200
Certificate type: PKCS#7
Chain: Microsoft Windows Production PCA 2011

Symbolic execution

Engine angr, status static_approximation, 0 paths explored at a maximum depth of 0. Vulnerability classes reached: 0. Exploitable paths: 1.

Frequently asked questions about acpi.sys

Is acpi.sys safe?

Based on DriverShield static and dynamic analysis, acpi.sys shows some suspicious signals and warrants manual review. Its composite risk score is 58/100 (verdict: suspicious). Always validate findings independently before acting.

What is the risk score of acpi.sys?

acpi.sys has a DriverShield composite risk score of 58/100, placing it in the suspicious verdict band. SHA256: 67d6b8d7b0fd4e356bcfa060e0862f9fca51ad541488c62891d55d97bbd9a5cc.

What is acpi.sys?

acpi.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.