atapi.sys - Clean (5/100) - DriverShield Analysis

Analysis of atapi.sys: clean verdict, risk score 5/100. 0 YARA matches. SHA256 9453c99632fea352. Kernel imports, IOCTL codes, MITRE ATT&CK, and code-signing details.

atapi.sys - Analysis Report

DriverShield analyzed the Windows kernel driver atapi.sys and assigned a verdict of Clean with a composite risk score of 5/100, indicating no notable risk signals (0-29 band).

Verdict	Clean (5/100)
YARA matches	0
File size	31200 bytes
Code-signing signer	Microsoft Windows
Analyzed	2026-03-22
SHA256	9453c99632fea352c877de61c6d0ee8d9d1ff13fdb9b290006e03abb1d82b5e9
SHA1	5dcf74c22f46b990b889f9ce839a643dc956a15c
MD5	81ff48994c82b1ca2c4ebd9c6c6683c4

Driver identity

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

File description	ATAPI IDE Miniport Driver
Product	Microsoft® Windows® Operating System
Company	Microsoft Corporation
Original filename	atapi.sys
Internal name	atapi.sys
File version	10.0.19041.3636 (WinBuild.160101.0800)
Copyright	© Microsoft Corporation. All rights reserved.

How the 5/100 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	0 / 100
Dangerous kernel imports	0 / 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

IOCTL dispatch codes (2)

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
0x00340394	medium	METHOD_BUFFERED	FILE_DEVICE_DISK Function #229

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	0x30B5	0x3200	6.09	CODE, EXEC, READ
.rdata	0x05A0	0x0600	4.24	IDATA, READ
.data	0x0090	0x0200	0.28	IDATA, READ, WRITE
.pdata	0x0264	0x0400	2.69	IDATA, READ
.idata	0x0434	0x0600	3.31	IDATA, READ
INIT	0x0072	0x0200	1.66	CODE, EXEC, READ, DISCARD
GFIDS	0x0078	0x0200	1.04	IDATA, READ, DISCARD
.rsrc	0x03F8	0x0400	3.37	IDATA, READ, DISCARD
.reloc	0x0280	0x0400	3.41	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.

MITRE ATT&CK techniques (3)

Techniques this driver could enable if loaded by an adversary.

ID	Technique	Tactic
T1071	Application Layer Protocol	Command and Control
T1543.003	Windows Service	Persistence
T1652	Device Driver Discovery	Discovery

Code-signing chain

Signer	Microsoft Windows
Signer organisation	Microsoft Corporation
Issuer	Microsoft Windows Production PCA 2011
Serial	33000004158295A1A3D82E2857000000000415
Valid from	2023-02-03 00:05 UTC
Valid until	2024-02-01 00:05 UTC (expired)
Signature validity	Not verified

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

Symbolic execution

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

Frequently asked questions about atapi.sys

Is atapi.sys safe?

Based on DriverShield static and dynamic analysis, atapi.sys is assessed as clean, with no notable risk signals. Its composite risk score is 5/100 (verdict: clean). Always validate findings independently before acting.

What is the risk score of atapi.sys?

atapi.sys has a DriverShield composite risk score of 5/100, placing it in the clean verdict band. SHA256: 9453c99632fea352c877de61c6d0ee8d9d1ff13fdb9b290006e03abb1d82b5e9.

What is atapi.sys?

atapi.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